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mariadb/sql/ha_partition.cc
Marko Mäkelä ab87fc6c7a Cleanup: Remove handler::update_table_comment() 
The only call of the virtual member function
handler::update_table_comment() was removed in
commit 82d28fada7 (MySQL 5.5.53)
but the implementation was not removed.

The only non-trivial implementation was for InnoDB. The information
is now returned via handler::get_foreign_key_create_info() and
ha_statistics::delete_length.
2021-05-27 09:31:19 +03:00

9237 lines
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/*
Copyright (c) 2005, 2019, Oracle and/or its affiliates.
Copyright (c) 2009, 2021, MariaDB
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; version 2 of the License.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335 USA
*/
/*
This handler was developed by Mikael Ronstrom for version 5.1 of MySQL.
It is an abstraction layer on top of other handlers such as MyISAM,
InnoDB, Federated, Berkeley DB and so forth. Partitioned tables can also
be handled by a storage engine. The current example of this is NDB
Cluster that has internally handled partitioning. This have benefits in
that many loops needed in the partition handler can be avoided.
Partitioning has an inherent feature which in some cases is positive and
in some cases is negative. It splits the data into chunks. This makes
the data more manageable, queries can easily be parallelised towards the
parts and indexes are split such that there are less levels in the
index trees. The inherent disadvantage is that to use a split index
one has to scan all index parts which is ok for large queries but for
small queries it can be a disadvantage.
Partitioning lays the foundation for more manageable databases that are
extremely large. It does also lay the foundation for more parallelism
in the execution of queries. This functionality will grow with later
versions of MySQL.
The partition is setup to use table locks. It implements an partition "SHARE"
that is inserted into a hash by table name. You can use this to store
information of state that any partition handler object will be able to see
if it is using the same table.
Please read the object definition in ha_partition.h before reading the rest
if this file.
*/
#include <my_global.h>
#include "sql_priv.h"
#include "sql_parse.h" // append_file_to_dir
#include "create_options.h"
#ifdef WITH_PARTITION_STORAGE_ENGINE
#include "ha_partition.h"
#include "sql_table.h" // tablename_to_filename
#include "key.h"
#include "sql_plugin.h"
#include "sql_show.h" // append_identifier
#include "sql_admin.h" // SQL_ADMIN_MSG_TEXT_SIZE
#include "debug_sync.h"
/* First 4 bytes in the .par file is the number of 32-bit words in the file */
#define PAR_WORD_SIZE 4
/* offset to the .par file checksum */
#define PAR_CHECKSUM_OFFSET 4
/* offset to the total number of partitions */
#define PAR_NUM_PARTS_OFFSET 8
/* offset to the engines array */
#define PAR_ENGINES_OFFSET 12
#define PARTITION_ENABLED_TABLE_FLAGS (HA_FILE_BASED | \
HA_REC_NOT_IN_SEQ | \
HA_CAN_REPAIR)
#define PARTITION_DISABLED_TABLE_FLAGS (HA_CAN_GEOMETRY | \
HA_CAN_FULLTEXT | \
HA_DUPLICATE_POS | \
HA_CAN_SQL_HANDLER | \
HA_CAN_INSERT_DELAYED | \
HA_READ_BEFORE_WRITE_REMOVAL)
static const char *ha_par_ext= ".par";
/****************************************************************************
MODULE create/delete handler object
****************************************************************************/
static handler *partition_create_handler(handlerton *hton,
TABLE_SHARE *share,
MEM_ROOT *mem_root);
static uint partition_flags();
static uint alter_table_flags(uint flags);
extern "C" int cmp_key_part_id(void *key_p, uchar *ref1, uchar *ref2);
extern "C" int cmp_key_rowid_part_id(void *ptr, uchar *ref1, uchar *ref2);
/*
If frm_error() is called then we will use this to to find out what file
extensions exist for the storage engine. This is also used by the default
rename_table and delete_table method in handler.cc.
*/
static const char *ha_partition_ext[]=
{
ha_par_ext, NullS
};
#ifdef HAVE_PSI_INTERFACE
PSI_mutex_key key_partition_auto_inc_mutex;
static PSI_mutex_info all_partition_mutexes[]=
{
{ &key_partition_auto_inc_mutex, "Partition_share::auto_inc_mutex", 0}
};
static void init_partition_psi_keys(void)
{
const char* category= "partition";
int count;
count= array_elements(all_partition_mutexes);
mysql_mutex_register(category, all_partition_mutexes, count);
}
#endif /* HAVE_PSI_INTERFACE */
static int partition_initialize(void *p)
{
handlerton *partition_hton;
partition_hton= (handlerton *)p;
partition_hton->state= SHOW_OPTION_YES;
partition_hton->db_type= DB_TYPE_PARTITION_DB;
partition_hton->create= partition_create_handler;
partition_hton->partition_flags= partition_flags;
partition_hton->alter_table_flags= alter_table_flags;
partition_hton->flags= HTON_NOT_USER_SELECTABLE |
HTON_HIDDEN |
HTON_TEMPORARY_NOT_SUPPORTED;
partition_hton->tablefile_extensions= ha_partition_ext;
#ifdef HAVE_PSI_INTERFACE
init_partition_psi_keys();
#endif
return 0;
}
/**
Initialize and allocate space for partitions shares.
@param num_parts Number of partitions to allocate storage for.
@return Operation status.
@retval true Failure (out of memory).
@retval false Success.
*/
bool Partition_share::init(uint num_parts)
{
DBUG_ENTER("Partition_share::init");
mysql_mutex_init(key_partition_auto_inc_mutex,
&auto_inc_mutex,
MY_MUTEX_INIT_FAST);
auto_inc_initialized= false;
partition_name_hash_initialized= false;
next_auto_inc_val= 0;
partitions_share_refs= new Parts_share_refs;
if (!partitions_share_refs)
DBUG_RETURN(true);
if (partitions_share_refs->init(num_parts))
{
delete partitions_share_refs;
DBUG_RETURN(true);
}
DBUG_RETURN(false);
}
/*
Create new partition handler
SYNOPSIS
partition_create_handler()
table Table object
RETURN VALUE
New partition object
*/
static handler *partition_create_handler(handlerton *hton,
TABLE_SHARE *share,
MEM_ROOT *mem_root)
{
ha_partition *file= new (mem_root) ha_partition(hton, share);
if (file && file->initialize_partition(mem_root))
{
delete file;
file= 0;
}
return file;
}
/*
HA_CAN_PARTITION:
Used by storage engines that can handle partitioning without this
partition handler
(Partition, NDB)
HA_CAN_UPDATE_PARTITION_KEY:
Set if the handler can update fields that are part of the partition
function.
HA_CAN_PARTITION_UNIQUE:
Set if the handler can handle unique indexes where the fields of the
unique key are not part of the fields of the partition function. Thus
a unique key can be set on all fields.
HA_USE_AUTO_PARTITION
Set if the handler sets all tables to be partitioned by default.
*/
static uint partition_flags()
{
return HA_CAN_PARTITION;
}
static uint alter_table_flags(uint flags __attribute__((unused)))
{
return (HA_PARTITION_FUNCTION_SUPPORTED |
HA_FAST_CHANGE_PARTITION);
}
const uint32 ha_partition::NO_CURRENT_PART_ID= NOT_A_PARTITION_ID;
/*
Constructor method
SYNOPSIS
ha_partition()
table Table object
RETURN VALUE
NONE
*/
ha_partition::ha_partition(handlerton *hton, TABLE_SHARE *share)
:handler(hton, share)
{
DBUG_ENTER("ha_partition::ha_partition(table)");
init_alloc_root(&m_mem_root, 512, 512, MYF(0));
init_handler_variables();
DBUG_VOID_RETURN;
}
/*
Constructor method
SYNOPSIS
ha_partition()
part_info Partition info
RETURN VALUE
NONE
*/
ha_partition::ha_partition(handlerton *hton, partition_info *part_info)
:handler(hton, NULL)
{
DBUG_ENTER("ha_partition::ha_partition(part_info)");
DBUG_ASSERT(part_info);
init_alloc_root(&m_mem_root, 512, 512, MYF(0));
init_handler_variables();
m_part_info= part_info;
m_create_handler= TRUE;
m_is_sub_partitioned= m_part_info->is_sub_partitioned();
DBUG_VOID_RETURN;
}
/**
ha_partition constructor method used by ha_partition::clone()
@param hton Handlerton (partition_hton)
@param share Table share object
@param part_info_arg partition_info to use
@param clone_arg ha_partition to clone
@param clme_mem_root_arg MEM_ROOT to use
@return New partition handler
*/
ha_partition::ha_partition(handlerton *hton, TABLE_SHARE *share,
partition_info *part_info_arg,
ha_partition *clone_arg,
MEM_ROOT *clone_mem_root_arg)
:handler(hton, share)
{
DBUG_ENTER("ha_partition::ha_partition(clone)");
init_alloc_root(&m_mem_root, 512, 512, MYF(0));
init_handler_variables();
m_part_info= part_info_arg;
m_create_handler= TRUE;
m_is_sub_partitioned= m_part_info->is_sub_partitioned();
m_is_clone_of= clone_arg;
m_clone_mem_root= clone_mem_root_arg;
part_share= clone_arg->part_share;
m_tot_parts= clone_arg->m_tot_parts;
m_pkey_is_clustered= clone_arg->primary_key_is_clustered();
DBUG_VOID_RETURN;
}
/*
Initialize handler object
SYNOPSIS
init_handler_variables()
RETURN VALUE
NONE
*/
void ha_partition::init_handler_variables()
{
active_index= MAX_KEY;
m_mode= 0;
m_open_test_lock= 0;
m_file_buffer= NULL;
m_name_buffer_ptr= NULL;
m_engine_array= NULL;
m_connect_string= NULL;
m_file= NULL;
m_file_tot_parts= 0;
m_reorged_file= NULL;
m_new_file= NULL;
m_reorged_parts= 0;
m_added_file= NULL;
m_tot_parts= 0;
m_pkey_is_clustered= 0;
m_part_spec.start_part= NO_CURRENT_PART_ID;
m_scan_value= 2;
m_ref_length= 0;
m_part_spec.end_part= NO_CURRENT_PART_ID;
m_index_scan_type= partition_no_index_scan;
m_start_key.key= NULL;
m_start_key.length= 0;
m_myisam= FALSE;
m_innodb= FALSE;
m_extra_cache= FALSE;
m_extra_cache_size= 0;
m_extra_prepare_for_update= FALSE;
m_extra_cache_part_id= NO_CURRENT_PART_ID;
m_handler_status= handler_not_initialized;
m_part_field_array= NULL;
m_ordered_rec_buffer= NULL;
m_top_entry= NO_CURRENT_PART_ID;
m_rec_length= 0;
m_last_part= 0;
m_rec0= 0;
m_err_rec= NULL;
m_curr_key_info[0]= NULL;
m_curr_key_info[1]= NULL;
m_part_func_monotonicity_info= NON_MONOTONIC;
auto_increment_lock= FALSE;
auto_increment_safe_stmt_log_lock= FALSE;
/*
this allows blackhole to work properly
*/
m_num_locks= 0;
m_part_info= NULL;
m_create_handler= FALSE;
m_is_sub_partitioned= 0;
m_is_clone_of= NULL;
m_clone_mem_root= NULL;
part_share= NULL;
m_new_partitions_share_refs.empty();
m_part_ids_sorted_by_num_of_records= NULL;
#ifdef DONT_HAVE_TO_BE_INITALIZED
m_start_key.flag= 0;
m_ordered= TRUE;
#endif
}
const char *ha_partition::table_type() const
{
// we can do this since we only support a single engine type
return m_file[0]->table_type();
}
/*
Destructor method
SYNOPSIS
~ha_partition()
RETURN VALUE
NONE
*/
ha_partition::~ha_partition()
{
DBUG_ENTER("ha_partition::~ha_partition");
if (m_new_partitions_share_refs.elements)
m_new_partitions_share_refs.delete_elements();
if (m_file != NULL)
{
uint i;
for (i= 0; i < m_tot_parts; i++)
delete m_file[i];
}
destroy_record_priority_queue();
my_free(m_part_ids_sorted_by_num_of_records);
if (m_added_file)
{
for (handler **ph= m_added_file; *ph; ph++)
delete (*ph);
}
clear_handler_file();
free_root(&m_mem_root, MYF(0));
DBUG_VOID_RETURN;
}
/*
Initialize partition handler object
SYNOPSIS
initialize_partition()
mem_root Allocate memory through this
RETURN VALUE
1 Error
0 Success
DESCRIPTION
The partition handler is only a layer on top of other engines. Thus it
can't really perform anything without the underlying handlers. Thus we
add this method as part of the allocation of a handler object.
1) Allocation of underlying handlers
If we have access to the partition info we will allocate one handler
instance for each partition.
2) Allocation without partition info
The cases where we don't have access to this information is when called
in preparation for delete_table and rename_table and in that case we
only need to set HA_FILE_BASED. In that case we will use the .par file
that contains information about the partitions and their engines and
the names of each partition.
3) Table flags initialisation
We need also to set table flags for the partition handler. This is not
static since it depends on what storage engines are used as underlying
handlers.
The table flags is set in this routine to simulate the behaviour of a
normal storage engine
The flag HA_FILE_BASED will be set independent of the underlying handlers
4) Index flags initialisation
When knowledge exists on the indexes it is also possible to initialize the
index flags. Again the index flags must be initialized by using the under-
lying handlers since this is storage engine dependent.
The flag HA_READ_ORDER will be reset for the time being to indicate no
ordered output is available from partition handler indexes. Later a merge
sort will be performed using the underlying handlers.
5) primary_key_is_clustered and has_transactions are
calculated here.
*/
bool ha_partition::initialize_partition(MEM_ROOT *mem_root)
{
handler **file_array, *file;
ulonglong check_table_flags;
DBUG_ENTER("ha_partition::initialize_partition");
if (m_create_handler)
{
m_tot_parts= m_part_info->get_tot_partitions();
DBUG_ASSERT(m_tot_parts > 0);
if (new_handlers_from_part_info(mem_root))
DBUG_RETURN(1);
}
else if (!table_share || !table_share->normalized_path.str)
{
/*
Called with dummy table share (delete, rename and alter table).
Don't need to set-up anything.
*/
DBUG_RETURN(0);
}
else if (get_from_handler_file(table_share->normalized_path.str,
mem_root, false))
{
my_error(ER_FAILED_READ_FROM_PAR_FILE, MYF(0));
DBUG_RETURN(1);
}
/*
We create all underlying table handlers here. We do it in this special
method to be able to report allocation errors.
Set up primary_key_is_clustered and
has_transactions since they are called often in all kinds of places,
other parameters are calculated on demand.
Verify that all partitions have the same table_flags.
*/
check_table_flags= m_file[0]->ha_table_flags();
m_pkey_is_clustered= TRUE;
file_array= m_file;
do
{
file= *file_array;
if (!file->primary_key_is_clustered())
m_pkey_is_clustered= FALSE;
if (check_table_flags != file->ha_table_flags())
{
my_error(ER_MIX_HANDLER_ERROR, MYF(0));
DBUG_RETURN(1);
}
} while (*(++file_array));
m_handler_status= handler_initialized;
DBUG_RETURN(0);
}
/****************************************************************************
MODULE meta data changes
****************************************************************************/
/*
Delete a table
SYNOPSIS
delete_table()
name Full path of table name
RETURN VALUE
>0 Error
0 Success
DESCRIPTION
Used to delete a table. By the time delete_table() has been called all
opened references to this table will have been closed (and your globally
shared references released. The variable name will just be the name of
the table. You will need to remove any files you have created at this
point.
If you do not implement this, the default delete_table() is called from
handler.cc and it will delete all files with the file extensions returned
by bas_ext().
Called from handler.cc by delete_table and ha_create_table(). Only used
during create if the table_flag HA_DROP_BEFORE_CREATE was specified for
the storage engine.
*/
int ha_partition::delete_table(const char *name)
{
DBUG_ENTER("ha_partition::delete_table");
DBUG_RETURN(del_ren_table(name, NULL));
}
/*
Rename a table
SYNOPSIS
rename_table()
from Full path of old table name
to Full path of new table name
RETURN VALUE
>0 Error
0 Success
DESCRIPTION
Renames a table from one name to another from alter table call.
If you do not implement this, the default rename_table() is called from
handler.cc and it will rename all files with the file extensions returned
by bas_ext().
Called from sql_table.cc by mysql_rename_table().
*/
int ha_partition::rename_table(const char *from, const char *to)
{
DBUG_ENTER("ha_partition::rename_table");
DBUG_RETURN(del_ren_table(from, to));
}
/*
Create the handler file (.par-file)
SYNOPSIS
create_partitioning_metadata()
name Full path of table name
create_info Create info generated for CREATE TABLE
RETURN VALUE
>0 Error
0 Success
DESCRIPTION
create_partitioning_metadata is called to create any handler specific files
before opening the file with openfrm to later call ::create on the
file object.
In the partition handler this is used to store the names of partitions
and types of engines in the partitions.
*/
int ha_partition::create_partitioning_metadata(const char *path,
const char *old_path,
int action_flag)
{
DBUG_ENTER("ha_partition::create_partitioning_metadata");
/*
We need to update total number of parts since we might write the handler
file as part of a partition management command
*/
if (action_flag == CHF_DELETE_FLAG ||
action_flag == CHF_RENAME_FLAG)
{
char name[FN_REFLEN];
char old_name[FN_REFLEN];
strxmov(name, path, ha_par_ext, NullS);
strxmov(old_name, old_path, ha_par_ext, NullS);
if ((action_flag == CHF_DELETE_FLAG &&
mysql_file_delete(key_file_partition, name, MYF(MY_WME))) ||
(action_flag == CHF_RENAME_FLAG &&
mysql_file_rename(key_file_partition, old_name, name, MYF(MY_WME))))
{
DBUG_RETURN(TRUE);
}
}
else if (action_flag == CHF_CREATE_FLAG)
{
if (create_handler_file(path))
{
my_error(ER_CANT_CREATE_HANDLER_FILE, MYF(0));
DBUG_RETURN(1);
}
}
DBUG_RETURN(0);
}
/*
Create a partitioned table
SYNOPSIS
create()
name Full path of table name
table_arg Table object
create_info Create info generated for CREATE TABLE
RETURN VALUE
>0 Error
0 Success
DESCRIPTION
create() is called to create a table. The variable name will have the name
of the table. When create() is called you do not need to worry about
opening the table. Also, the FRM file will have already been created so
adjusting create_info will not do you any good. You can overwrite the frm
file at this point if you wish to change the table definition, but there
are no methods currently provided for doing that.
Called from handler.cc by ha_create_table().
*/
int ha_partition::create(const char *name, TABLE *table_arg,
HA_CREATE_INFO *create_info)
{
int error;
char name_buff[FN_REFLEN + 1], name_lc_buff[FN_REFLEN];
char *name_buffer_ptr;
const char *path;
uint i;
List_iterator_fast <partition_element> part_it(m_part_info->partitions);
partition_element *part_elem;
handler **file, **abort_file;
DBUG_ENTER("ha_partition::create");
DBUG_ASSERT(*fn_rext((char*)name) == '\0');
/* Not allowed to create temporary partitioned tables */
if (create_info && create_info->tmp_table())
{
my_error(ER_PARTITION_NO_TEMPORARY, MYF(0));
DBUG_RETURN(TRUE);
}
if (get_from_handler_file(name, ha_thd()->mem_root, false))
DBUG_RETURN(TRUE);
DBUG_ASSERT(m_file_buffer);
DBUG_PRINT("enter", ("name: (%s)", name));
name_buffer_ptr= m_name_buffer_ptr;
file= m_file;
/*
Since ha_partition has HA_FILE_BASED, it must alter underlying table names
if they do not have HA_FILE_BASED and lower_case_table_names == 2.
See Bug#37402, for Mac OS X.
The appended #P#<partname>[#SP#<subpartname>] will remain in current case.
Using the first partitions handler, since mixing handlers is not allowed.
*/
path= get_canonical_filename(*file, name, name_lc_buff);
for (i= 0; i < m_part_info->num_parts; i++)
{
part_elem= part_it++;
if (m_is_sub_partitioned)
{
uint j;
List_iterator_fast <partition_element> sub_it(part_elem->subpartitions);
for (j= 0; j < m_part_info->num_subparts; j++)
{
part_elem= sub_it++;
if ((error= create_partition_name(name_buff, sizeof(name_buff), path,
name_buffer_ptr, NORMAL_PART_NAME, FALSE)))
goto create_error;
if ((error= set_up_table_before_create(table_arg, name_buff,
create_info, part_elem)) ||
((error= (*file)->ha_create(name_buff, table_arg, create_info))))
goto create_error;
name_buffer_ptr= strend(name_buffer_ptr) + 1;
file++;
}
}
else
{
if ((error= create_partition_name(name_buff, sizeof(name_buff), path,
name_buffer_ptr, NORMAL_PART_NAME, FALSE)))
goto create_error;
if ((error= set_up_table_before_create(table_arg, name_buff,
create_info, part_elem)) ||
((error= (*file)->ha_create(name_buff, table_arg, create_info))))
goto create_error;
name_buffer_ptr= strend(name_buffer_ptr) + 1;
file++;
}
}
DBUG_RETURN(0);
create_error:
name_buffer_ptr= m_name_buffer_ptr;
for (abort_file= file, file= m_file; file < abort_file; file++)
{
if (!create_partition_name(name_buff, sizeof(name_buff), path,
name_buffer_ptr, NORMAL_PART_NAME, FALSE))
(void) (*file)->ha_delete_table((const char*) name_buff);
name_buffer_ptr= strend(name_buffer_ptr) + 1;
}
handler::delete_table(name);
DBUG_RETURN(error);
}
/*
Drop partitions as part of ALTER TABLE of partitions
SYNOPSIS
drop_partitions()
path Complete path of db and table name
RETURN VALUE
>0 Failure
0 Success
DESCRIPTION
Use part_info object on handler object to deduce which partitions to
drop (each partition has a state attached to it)
*/
int ha_partition::drop_partitions(const char *path)
{
List_iterator<partition_element> part_it(m_part_info->partitions);
char part_name_buff[FN_REFLEN + 1];
uint num_parts= m_part_info->partitions.elements;
uint num_subparts= m_part_info->num_subparts;
uint i= 0;
uint name_variant;
int ret_error;
int error= 0;
DBUG_ENTER("ha_partition::drop_partitions");
/*
Assert that it works without HA_FILE_BASED and lower_case_table_name = 2.
We use m_file[0] as long as all partitions have the same storage engine.
*/
DBUG_ASSERT(!strcmp(path, get_canonical_filename(m_file[0], path,
part_name_buff)));
do
{
partition_element *part_elem= part_it++;
if (part_elem->part_state == PART_TO_BE_DROPPED)
{
handler *file;
/*
This part is to be dropped, meaning the part or all its subparts.
*/
name_variant= NORMAL_PART_NAME;
if (m_is_sub_partitioned)
{
List_iterator<partition_element> sub_it(part_elem->subpartitions);
uint j= 0, part;
do
{
partition_element *sub_elem= sub_it++;
part= i * num_subparts + j;
if ((ret_error= create_subpartition_name(part_name_buff,
sizeof(part_name_buff), path,
part_elem->partition_name,
sub_elem->partition_name, name_variant)))
error= ret_error;
file= m_file[part];
DBUG_PRINT("info", ("Drop subpartition %s", part_name_buff));
if ((ret_error= file->ha_delete_table(part_name_buff)))
error= ret_error;
if (deactivate_ddl_log_entry(sub_elem->log_entry->entry_pos))
error= 1;
} while (++j < num_subparts);
}
else
{
if ((ret_error= create_partition_name(part_name_buff,
sizeof(part_name_buff), path,
part_elem->partition_name, name_variant, TRUE)))
error= ret_error;
else
{
file= m_file[i];
DBUG_PRINT("info", ("Drop partition %s", part_name_buff));
if ((ret_error= file->ha_delete_table(part_name_buff)))
error= ret_error;
if (deactivate_ddl_log_entry(part_elem->log_entry->entry_pos))
error= 1;
}
}
if (part_elem->part_state == PART_IS_CHANGED)
part_elem->part_state= PART_NORMAL;
else
part_elem->part_state= PART_IS_DROPPED;
}
} while (++i < num_parts);
(void) sync_ddl_log();
DBUG_RETURN(error);
}
/*
Rename partitions as part of ALTER TABLE of partitions
SYNOPSIS
rename_partitions()
path Complete path of db and table name
RETURN VALUE
TRUE Failure
FALSE Success
DESCRIPTION
When reorganising partitions, adding hash partitions and coalescing
partitions it can be necessary to rename partitions while holding
an exclusive lock on the table.
Which partitions to rename is given by state of partitions found by the
partition info struct referenced from the handler object
*/
int ha_partition::rename_partitions(const char *path)
{
List_iterator<partition_element> part_it(m_part_info->partitions);
List_iterator<partition_element> temp_it(m_part_info->temp_partitions);
char part_name_buff[FN_REFLEN + 1];
char norm_name_buff[FN_REFLEN + 1];
uint num_parts= m_part_info->partitions.elements;
uint part_count= 0;
uint num_subparts= m_part_info->num_subparts;
uint i= 0;
uint j= 0;
int error= 0;
int ret_error;
uint temp_partitions= m_part_info->temp_partitions.elements;
handler *file;
partition_element *part_elem, *sub_elem;
DBUG_ENTER("ha_partition::rename_partitions");
/*
Assert that it works without HA_FILE_BASED and lower_case_table_name = 2.
We use m_file[0] as long as all partitions have the same storage engine.
*/
DBUG_ASSERT(!strcmp(path, get_canonical_filename(m_file[0], path,
norm_name_buff)));
DEBUG_SYNC(ha_thd(), "before_rename_partitions");
if (temp_partitions)
{
/*
These are the reorganised partitions that have already been copied.
We delete the partitions and log the delete by inactivating the
delete log entry in the table log. We only need to synchronise
these writes before moving to the next loop since there is no
interaction among reorganised partitions, they cannot have the
same name.
*/
do
{
part_elem= temp_it++;
if (m_is_sub_partitioned)
{
List_iterator<partition_element> sub_it(part_elem->subpartitions);
j= 0;
do
{
sub_elem= sub_it++;
file= m_reorged_file[part_count++];
if ((ret_error= create_subpartition_name(norm_name_buff,
sizeof(norm_name_buff), path,
part_elem->partition_name,
sub_elem->partition_name, NORMAL_PART_NAME)))
error= ret_error;
DBUG_PRINT("info", ("Delete subpartition %s", norm_name_buff));
if ((ret_error= file->ha_delete_table(norm_name_buff)))
error= ret_error;
else if (deactivate_ddl_log_entry(sub_elem->log_entry->entry_pos))
error= 1;
else
sub_elem->log_entry= NULL; /* Indicate success */
} while (++j < num_subparts);
}
else
{
file= m_reorged_file[part_count++];
if ((ret_error= create_partition_name(norm_name_buff,
sizeof(norm_name_buff), path,
part_elem->partition_name, NORMAL_PART_NAME, TRUE)))
error= ret_error;
else
{
DBUG_PRINT("info", ("Delete partition %s", norm_name_buff));
if ((ret_error= file->ha_delete_table(norm_name_buff)))
error= ret_error;
else if (deactivate_ddl_log_entry(part_elem->log_entry->entry_pos))
error= 1;
else
part_elem->log_entry= NULL; /* Indicate success */
}
}
} while (++i < temp_partitions);
(void) sync_ddl_log();
}
i= 0;
do
{
/*
When state is PART_IS_CHANGED it means that we have created a new
TEMP partition that is to be renamed to normal partition name and
we are to delete the old partition with currently the normal name.
We perform this operation by
1) Delete old partition with normal partition name
2) Signal this in table log entry
3) Synch table log to ensure we have consistency in crashes
4) Rename temporary partition name to normal partition name
5) Signal this to table log entry
It is not necessary to synch the last state since a new rename
should not corrupt things if there was no temporary partition.
The only other parts we need to cater for are new parts that
replace reorganised parts. The reorganised parts were deleted
by the code above that goes through the temp_partitions list.
Thus the synch above makes it safe to simply perform step 4 and 5
for those entries.
*/
part_elem= part_it++;
if (part_elem->part_state == PART_IS_CHANGED ||
part_elem->part_state == PART_TO_BE_DROPPED ||
(part_elem->part_state == PART_IS_ADDED && temp_partitions))
{
if (m_is_sub_partitioned)
{
List_iterator<partition_element> sub_it(part_elem->subpartitions);
uint part;
j= 0;
do
{
sub_elem= sub_it++;
part= i * num_subparts + j;
if ((ret_error= create_subpartition_name(norm_name_buff,
sizeof(norm_name_buff), path,
part_elem->partition_name,
sub_elem->partition_name, NORMAL_PART_NAME)))
error= ret_error;
if (part_elem->part_state == PART_IS_CHANGED)
{
file= m_reorged_file[part_count++];
DBUG_PRINT("info", ("Delete subpartition %s", norm_name_buff));
if ((ret_error= file->ha_delete_table(norm_name_buff)))
error= ret_error;
else if (deactivate_ddl_log_entry(sub_elem->log_entry->entry_pos))
error= 1;
(void) sync_ddl_log();
}
file= m_new_file[part];
if ((ret_error= create_subpartition_name(part_name_buff,
sizeof(part_name_buff), path,
part_elem->partition_name,
sub_elem->partition_name, TEMP_PART_NAME)))
error= ret_error;
DBUG_PRINT("info", ("Rename subpartition from %s to %s",
part_name_buff, norm_name_buff));
if ((ret_error= file->ha_rename_table(part_name_buff,
norm_name_buff)))
error= ret_error;
else if (deactivate_ddl_log_entry(sub_elem->log_entry->entry_pos))
error= 1;
else
sub_elem->log_entry= NULL;
} while (++j < num_subparts);
}
else
{
if ((ret_error= create_partition_name(norm_name_buff,
sizeof(norm_name_buff), path,
part_elem->partition_name, NORMAL_PART_NAME, TRUE)) ||
(ret_error= create_partition_name(part_name_buff,
sizeof(part_name_buff), path,
part_elem->partition_name, TEMP_PART_NAME, TRUE)))
error= ret_error;
else
{
if (part_elem->part_state == PART_IS_CHANGED)
{
file= m_reorged_file[part_count++];
DBUG_PRINT("info", ("Delete partition %s", norm_name_buff));
if ((ret_error= file->ha_delete_table(norm_name_buff)))
error= ret_error;
else if (deactivate_ddl_log_entry(part_elem->log_entry->entry_pos))
error= 1;
(void) sync_ddl_log();
}
file= m_new_file[i];
DBUG_PRINT("info", ("Rename partition from %s to %s",
part_name_buff, norm_name_buff));
if ((ret_error= file->ha_rename_table(part_name_buff,
norm_name_buff)))
error= ret_error;
else if (deactivate_ddl_log_entry(part_elem->log_entry->entry_pos))
error= 1;
else
part_elem->log_entry= NULL;
}
}
}
} while (++i < num_parts);
(void) sync_ddl_log();
DBUG_RETURN(error);
}
#define OPTIMIZE_PARTS 1
#define ANALYZE_PARTS 2
#define CHECK_PARTS 3
#define REPAIR_PARTS 4
#define ASSIGN_KEYCACHE_PARTS 5
#define PRELOAD_KEYS_PARTS 6
static const char *opt_op_name[]= {NULL,
"optimize", "analyze", "check", "repair",
"assign_to_keycache", "preload_keys"};
/*
Optimize table
SYNOPSIS
optimize()
thd Thread object
check_opt Check/analyze/repair/optimize options
RETURN VALUES
>0 Error
0 Success
*/
int ha_partition::optimize(THD *thd, HA_CHECK_OPT *check_opt)
{
DBUG_ENTER("ha_partition::optimize");
DBUG_RETURN(handle_opt_partitions(thd, check_opt, OPTIMIZE_PARTS));
}
/*
Analyze table
SYNOPSIS
analyze()
thd Thread object
check_opt Check/analyze/repair/optimize options
RETURN VALUES
>0 Error
0 Success
*/
int ha_partition::analyze(THD *thd, HA_CHECK_OPT *check_opt)
{
DBUG_ENTER("ha_partition::analyze");
DBUG_RETURN(handle_opt_partitions(thd, check_opt, ANALYZE_PARTS));
}
/*
Check table
SYNOPSIS
check()
thd Thread object
check_opt Check/analyze/repair/optimize options
RETURN VALUES
>0 Error
0 Success
*/
int ha_partition::check(THD *thd, HA_CHECK_OPT *check_opt)
{
DBUG_ENTER("ha_partition::check");
DBUG_RETURN(handle_opt_partitions(thd, check_opt, CHECK_PARTS));
}
/*
Repair table
SYNOPSIS
repair()
thd Thread object
check_opt Check/analyze/repair/optimize options
RETURN VALUES
>0 Error
0 Success
*/
int ha_partition::repair(THD *thd, HA_CHECK_OPT *check_opt)
{
DBUG_ENTER("ha_partition::repair");
int res= handle_opt_partitions(thd, check_opt, REPAIR_PARTS);
DBUG_RETURN(res);
}
/**
Assign to keycache
@param thd Thread object
@param check_opt Check/analyze/repair/optimize options
@return
@retval >0 Error
@retval 0 Success
*/
int ha_partition::assign_to_keycache(THD *thd, HA_CHECK_OPT *check_opt)
{
DBUG_ENTER("ha_partition::assign_to_keycache");
DBUG_RETURN(handle_opt_partitions(thd, check_opt, ASSIGN_KEYCACHE_PARTS));
}
/**
Preload to keycache
@param thd Thread object
@param check_opt Check/analyze/repair/optimize options
@return
@retval >0 Error
@retval 0 Success
*/
int ha_partition::preload_keys(THD *thd, HA_CHECK_OPT *check_opt)
{
DBUG_ENTER("ha_partition::preload_keys");
DBUG_RETURN(handle_opt_partitions(thd, check_opt, PRELOAD_KEYS_PARTS));
}
/*
Handle optimize/analyze/check/repair of one partition
SYNOPSIS
handle_opt_part()
thd Thread object
check_opt Options
file Handler object of partition
flag Optimize/Analyze/Check/Repair flag
RETURN VALUE
>0 Failure
0 Success
*/
int ha_partition::handle_opt_part(THD *thd, HA_CHECK_OPT *check_opt,
uint part_id, uint flag)
{
int error;
handler *file= m_file[part_id];
DBUG_ENTER("handle_opt_part");
DBUG_PRINT("enter", ("flag = %u", flag));
if (flag == OPTIMIZE_PARTS)
error= file->ha_optimize(thd, check_opt);
else if (flag == ANALYZE_PARTS)
error= file->ha_analyze(thd, check_opt);
else if (flag == CHECK_PARTS)
{
error= file->ha_check(thd, check_opt);
if (!error ||
error == HA_ADMIN_ALREADY_DONE ||
error == HA_ADMIN_NOT_IMPLEMENTED)
{
if (check_opt->flags & (T_MEDIUM | T_EXTEND))
error= check_misplaced_rows(part_id, false);
}
}
else if (flag == REPAIR_PARTS)
{
error= file->ha_repair(thd, check_opt);
if (!error ||
error == HA_ADMIN_ALREADY_DONE ||
error == HA_ADMIN_NOT_IMPLEMENTED)
{
if (check_opt->flags & (T_MEDIUM | T_EXTEND))
error= check_misplaced_rows(part_id, true);
}
}
else if (flag == ASSIGN_KEYCACHE_PARTS)
error= file->assign_to_keycache(thd, check_opt);
else if (flag == PRELOAD_KEYS_PARTS)
error= file->preload_keys(thd, check_opt);
else
{
DBUG_ASSERT(FALSE);
error= 1;
}
if (error == HA_ADMIN_ALREADY_DONE)
error= 0;
DBUG_RETURN(error);
}
/*
print a message row formatted for ANALYZE/CHECK/OPTIMIZE/REPAIR TABLE
(modelled after mi_check_print_msg)
TODO: move this into the handler, or rewrite mysql_admin_table.
*/
static bool print_admin_msg(THD* thd, uint len,
const char* msg_type,
const char* db_name, String &table_name,
const char* op_name, const char *fmt, ...)
ATTRIBUTE_FORMAT(printf, 7, 8);
static bool print_admin_msg(THD* thd, uint len,
const char* msg_type,
const char* db_name, String &table_name,
const char* op_name, const char *fmt, ...)
{
va_list args;
Protocol *protocol= thd->protocol;
uint length;
uint msg_length;
char name[NAME_LEN*2+2];
char *msgbuf;
bool error= true;
if (!(msgbuf= (char*) my_malloc(len, MYF(0))))
return true;
va_start(args, fmt);
msg_length= my_vsnprintf(msgbuf, len, fmt, args);
va_end(args);
if (msg_length >= (len - 1))
goto err;
msgbuf[len - 1] = 0; // healthy paranoia
if (!thd->vio_ok())
{
sql_print_error("%s", msgbuf);
goto err;
}
length=(uint) (strxmov(name, db_name, ".", table_name.c_ptr_safe(), NullS) - name);
/*
TODO: switch from protocol to push_warning here. The main reason we didn't
it yet is parallel repair, which threads have no THD object accessible via
current_thd.
Also we likely need to lock mutex here (in both cases with protocol and
push_warning).
*/
DBUG_PRINT("info",("print_admin_msg: %s, %s, %s, %s", name, op_name,
msg_type, msgbuf));
protocol->prepare_for_resend();
protocol->store(name, length, system_charset_info);
protocol->store(op_name, system_charset_info);
protocol->store(msg_type, system_charset_info);
protocol->store(msgbuf, msg_length, system_charset_info);
if (protocol->write())
{
sql_print_error("Failed on my_net_write, writing to stderr instead: %s\n",
msgbuf);
goto err;
}
error= false;
err:
my_free(msgbuf);
return error;
}
/*
Handle optimize/analyze/check/repair of partitions
SYNOPSIS
handle_opt_partitions()
thd Thread object
check_opt Options
flag Optimize/Analyze/Check/Repair flag
RETURN VALUE
>0 Failure
0 Success
*/
int ha_partition::handle_opt_partitions(THD *thd, HA_CHECK_OPT *check_opt,
uint flag)
{
List_iterator<partition_element> part_it(m_part_info->partitions);
uint num_parts= m_part_info->num_parts;
uint num_subparts= m_part_info->num_subparts;
uint i= 0;
int error;
DBUG_ENTER("ha_partition::handle_opt_partitions");
DBUG_PRINT("enter", ("flag= %u", flag));
do
{
partition_element *part_elem= part_it++;
/*
when ALTER TABLE <CMD> PARTITION ...
it should only do named partitions, otherwise all partitions
*/
if (!(thd->lex->alter_info.flags & Alter_info::ALTER_ADMIN_PARTITION) ||
part_elem->part_state == PART_ADMIN)
{
if (m_is_sub_partitioned)
{
List_iterator<partition_element> subpart_it(part_elem->subpartitions);
partition_element *sub_elem;
uint j= 0, part;
do
{
sub_elem= subpart_it++;
part= i * num_subparts + j;
DBUG_PRINT("info", ("Optimize subpartition %u (%s)",
part, sub_elem->partition_name));
if ((error= handle_opt_part(thd, check_opt, part, flag)))
{
/* print a line which partition the error belongs to */
if (error != HA_ADMIN_NOT_IMPLEMENTED &&
error != HA_ADMIN_ALREADY_DONE &&
error != HA_ADMIN_TRY_ALTER)
{
print_admin_msg(thd, MYSQL_ERRMSG_SIZE, "error",
table_share->db.str, table->alias,
opt_op_name[flag],
"Subpartition %s returned error",
sub_elem->partition_name);
}
/* reset part_state for the remaining partitions */
do
{
if (part_elem->part_state == PART_ADMIN)
part_elem->part_state= PART_NORMAL;
} while ((part_elem= part_it++));
DBUG_RETURN(error);
}
} while (++j < num_subparts);
}
else
{
DBUG_PRINT("info", ("Optimize partition %u (%s)", i,
part_elem->partition_name));
if ((error= handle_opt_part(thd, check_opt, i, flag)))
{
/* print a line which partition the error belongs to */
if (error != HA_ADMIN_NOT_IMPLEMENTED &&
error != HA_ADMIN_ALREADY_DONE &&
error != HA_ADMIN_TRY_ALTER)
{
print_admin_msg(thd, MYSQL_ERRMSG_SIZE, "error",
table_share->db.str, table->alias,
opt_op_name[flag], "Partition %s returned error",
part_elem->partition_name);
}
/* reset part_state for the remaining partitions */
do
{
if (part_elem->part_state == PART_ADMIN)
part_elem->part_state= PART_NORMAL;
} while ((part_elem= part_it++));
DBUG_RETURN(error);
}
}
part_elem->part_state= PART_NORMAL;
}
} while (++i < num_parts);
DBUG_RETURN(FALSE);
}
/**
@brief Check and repair the table if necessary
@param thd Thread object
@retval TRUE Error/Not supported
@retval FALSE Success
@note Called if open_table_from_share fails and ::is_crashed().
*/
bool ha_partition::check_and_repair(THD *thd)
{
handler **file= m_file;
DBUG_ENTER("ha_partition::check_and_repair");
do
{
if ((*file)->ha_check_and_repair(thd))
DBUG_RETURN(TRUE);
} while (*(++file));
DBUG_RETURN(FALSE);
}
/**
@breif Check if the table can be automatically repaired
@retval TRUE Can be auto repaired
@retval FALSE Cannot be auto repaired
*/
bool ha_partition::auto_repair(int error) const
{
DBUG_ENTER("ha_partition::auto_repair");
/*
As long as we only support one storage engine per table,
we can use the first partition for this function.
*/
DBUG_RETURN(m_file[0]->auto_repair(error));
}
/**
@breif Check if the table is crashed
@retval TRUE Crashed
@retval FALSE Not crashed
*/
bool ha_partition::is_crashed() const
{
handler **file= m_file;
DBUG_ENTER("ha_partition::is_crashed");
do
{
if ((*file)->is_crashed())
DBUG_RETURN(TRUE);
} while (*(++file));
DBUG_RETURN(FALSE);
}
/*
Prepare by creating a new partition
SYNOPSIS
prepare_new_partition()
table Table object
create_info Create info from CREATE TABLE
file Handler object of new partition
part_name partition name
RETURN VALUE
>0 Error
0 Success
*/
int ha_partition::prepare_new_partition(TABLE *tbl,
HA_CREATE_INFO *create_info,
handler *file, const char *part_name,
partition_element *p_elem,
uint disable_non_uniq_indexes)
{
int error;
DBUG_ENTER("prepare_new_partition");
/*
This call to set_up_table_before_create() is done for an alter table.
So this may be the second time around for this partition_element,
depending on how many partitions and subpartitions there were before,
and how many there are now.
The first time, on the CREATE, data_file_name and index_file_name
came from the parser. They did not have the file name attached to
the end. But if this partition is less than the total number of
previous partitions, it's data_file_name has the filename attached.
So we need to take the partition filename off if it exists.
That file name may be different from part_name, which will be
attached in append_file_to_dir().
*/
truncate_partition_filename(p_elem->data_file_name);
truncate_partition_filename(p_elem->index_file_name);
if ((error= set_up_table_before_create(tbl, part_name, create_info, p_elem)))
goto error_create;
tbl->s->connect_string = p_elem->connect_string;
if ((error= file->ha_create(part_name, tbl, create_info)))
{
/*
Added for safety, InnoDB reports HA_ERR_FOUND_DUPP_KEY
if the table/partition already exists.
If we return that error code, then print_error would try to
get_dup_key on a non-existing partition.
So return a more reasonable error code.
*/
if (error == HA_ERR_FOUND_DUPP_KEY)
error= HA_ERR_TABLE_EXIST;
goto error_create;
}
DBUG_PRINT("info", ("partition %s created", part_name));
if ((error= file->ha_open(tbl, part_name, m_mode,
m_open_test_lock | HA_OPEN_NO_PSI_CALL)))
goto error_open;
DBUG_PRINT("info", ("partition %s opened", part_name));
/*
Note: if you plan to add another call that may return failure,
better to do it before external_lock() as cleanup_new_partition()
assumes that external_lock() is last call that may fail here.
Otherwise see description for cleanup_new_partition().
*/
if ((error= file->ha_external_lock(ha_thd(), F_WRLCK)))
goto error_external_lock;
DBUG_PRINT("info", ("partition %s external locked", part_name));
if (disable_non_uniq_indexes)
file->ha_disable_indexes(HA_KEY_SWITCH_NONUNIQ_SAVE);
DBUG_RETURN(0);
error_external_lock:
(void) file->ha_close();
error_open:
(void) file->ha_delete_table(part_name);
error_create:
DBUG_RETURN(error);
}
/*
Cleanup by removing all created partitions after error
SYNOPSIS
cleanup_new_partition()
part_count Number of partitions to remove
RETURN VALUE
NONE
DESCRIPTION
This function is called immediately after prepare_new_partition() in
case the latter fails.
In prepare_new_partition() last call that may return failure is
external_lock(). That means if prepare_new_partition() fails,
partition does not have external lock. Thus no need to call
external_lock(F_UNLCK) here.
TODO:
We must ensure that in the case that we get an error during the process
that we call external_lock with F_UNLCK, close the table and delete the
table in the case where we have been successful with prepare_handler.
We solve this by keeping an array of successful calls to prepare_handler
which can then be used to undo the call.
*/
void ha_partition::cleanup_new_partition(uint part_count)
{
DBUG_ENTER("ha_partition::cleanup_new_partition");
if (m_added_file)
{
THD *thd= ha_thd();
handler **file= m_added_file;
while ((part_count > 0) && (*file))
{
(*file)->ha_external_lock(thd, F_UNLCK);
(*file)->ha_close();
/* Leave the (*file)->ha_delete_table(part_name) to the ddl-log */
file++;
part_count--;
}
m_added_file= NULL;
}
DBUG_VOID_RETURN;
}
/*
Implement the partition changes defined by ALTER TABLE of partitions
SYNOPSIS
change_partitions()
create_info HA_CREATE_INFO object describing all
fields and indexes in table
path Complete path of db and table name
out: copied Output parameter where number of copied
records are added
out: deleted Output parameter where number of deleted
records are added
pack_frm_data Reference to packed frm file
pack_frm_len Length of packed frm file
RETURN VALUE
>0 Failure
0 Success
DESCRIPTION
Add and copy if needed a number of partitions, during this operation
no other operation is ongoing in the server. This is used by
ADD PARTITION all types as well as by REORGANIZE PARTITION. For
one-phased implementations it is used also by DROP and COALESCE
PARTITIONs.
One-phased implementation needs the new frm file, other handlers will
get zero length and a NULL reference here.
*/
int ha_partition::change_partitions(HA_CREATE_INFO *create_info,
const char *path,
ulonglong * const copied,
ulonglong * const deleted,
const uchar *pack_frm_data
__attribute__((unused)),
size_t pack_frm_len
__attribute__((unused)))
{
List_iterator<partition_element> part_it(m_part_info->partitions);
List_iterator <partition_element> t_it(m_part_info->temp_partitions);
char part_name_buff[FN_REFLEN + 1];
uint num_parts= m_part_info->partitions.elements;
uint num_subparts= m_part_info->num_subparts;
uint i= 0;
uint num_remain_partitions, part_count, orig_count;
handler **new_file_array;
int error= 1;
bool first;
uint temp_partitions= m_part_info->temp_partitions.elements;
THD *thd= ha_thd();
DBUG_ENTER("ha_partition::change_partitions");
/*
Assert that it works without HA_FILE_BASED and lower_case_table_name = 2.
We use m_file[0] as long as all partitions have the same storage engine.
*/
DBUG_ASSERT(!strcmp(path, get_canonical_filename(m_file[0], path,
part_name_buff)));
m_reorged_parts= 0;
if (!m_part_info->is_sub_partitioned())
num_subparts= 1;
/*
Step 1:
Calculate number of reorganised partitions and allocate space for
their handler references.
*/
if (temp_partitions)
{
m_reorged_parts= temp_partitions * num_subparts;
}
else
{
do
{
partition_element *part_elem= part_it++;
if (part_elem->part_state == PART_CHANGED ||
part_elem->part_state == PART_REORGED_DROPPED)
{
m_reorged_parts+= num_subparts;
}
} while (++i < num_parts);
}
if (m_reorged_parts &&
!(m_reorged_file= (handler**) thd->calloc(sizeof(handler*)*
(m_reorged_parts + 1))))
{
mem_alloc_error(sizeof(handler*)*(m_reorged_parts+1));
DBUG_RETURN(HA_ERR_OUT_OF_MEM);
}
/*
Step 2:
Calculate number of partitions after change and allocate space for
their handler references.
*/
num_remain_partitions= 0;
if (temp_partitions)
{
num_remain_partitions= num_parts * num_subparts;
}
else
{
part_it.rewind();
i= 0;
do
{
partition_element *part_elem= part_it++;
if (part_elem->part_state == PART_NORMAL ||
part_elem->part_state == PART_TO_BE_ADDED ||
part_elem->part_state == PART_CHANGED)
{
num_remain_partitions+= num_subparts;
}
} while (++i < num_parts);
}
if (!(new_file_array= ((handler**)
thd->calloc(sizeof(handler*)*
(2*(num_remain_partitions + 1))))))
{
mem_alloc_error(sizeof(handler*)*2*(num_remain_partitions+1));
DBUG_RETURN(HA_ERR_OUT_OF_MEM);
}
m_added_file= &new_file_array[num_remain_partitions + 1];
/*
Step 3:
Fill m_reorged_file with handler references and NULL at the end
*/
if (m_reorged_parts)
{
i= 0;
part_count= 0;
first= TRUE;
part_it.rewind();
do
{
partition_element *part_elem= part_it++;
if (part_elem->part_state == PART_CHANGED ||
part_elem->part_state == PART_REORGED_DROPPED)
{
memcpy((void*)&m_reorged_file[part_count],
(void*)&m_file[i*num_subparts],
sizeof(handler*)*num_subparts);
part_count+= num_subparts;
}
else if (first && temp_partitions &&
part_elem->part_state == PART_TO_BE_ADDED)
{
/*
When doing an ALTER TABLE REORGANIZE PARTITION a number of
partitions is to be reorganised into a set of new partitions.
The reorganised partitions are in this case in the temp_partitions
list. We copy all of them in one batch and thus we only do this
until we find the first partition with state PART_TO_BE_ADDED
since this is where the new partitions go in and where the old
ones used to be.
*/
first= FALSE;
DBUG_ASSERT(((i*num_subparts) + m_reorged_parts) <= m_file_tot_parts);
memcpy((void*)m_reorged_file, &m_file[i*num_subparts],
sizeof(handler*)*m_reorged_parts);
}
} while (++i < num_parts);
}
/*
Step 4:
Fill new_array_file with handler references. Create the handlers if
needed.
*/
i= 0;
part_count= 0;
orig_count= 0;
first= TRUE;
part_it.rewind();
do
{
partition_element *part_elem= part_it++;
if (part_elem->part_state == PART_NORMAL)
{
DBUG_ASSERT(orig_count + num_subparts <= m_file_tot_parts);
memcpy((void*)&new_file_array[part_count], (void*)&m_file[orig_count],
sizeof(handler*)*num_subparts);
part_count+= num_subparts;
orig_count+= num_subparts;
}
else if (part_elem->part_state == PART_CHANGED ||
part_elem->part_state == PART_TO_BE_ADDED)
{
uint j= 0;
Parts_share_refs *p_share_refs;
/*
The Handler_shares for each partition's handler can be allocated
within this handler, since there will not be any more instances of the
new partitions, until the table is reopened after the ALTER succeeded.
*/
p_share_refs= new Parts_share_refs;
if (!p_share_refs)
DBUG_RETURN(HA_ERR_OUT_OF_MEM);
if (p_share_refs->init(num_subparts))
DBUG_RETURN(HA_ERR_OUT_OF_MEM);
if (m_new_partitions_share_refs.push_back(p_share_refs, thd->mem_root))
DBUG_RETURN(HA_ERR_OUT_OF_MEM);
do
{
handler **new_file= &new_file_array[part_count++];
if (!(*new_file=
get_new_handler(table->s,
thd->mem_root,
part_elem->engine_type)))
{
mem_alloc_error(sizeof(handler));
DBUG_RETURN(HA_ERR_OUT_OF_MEM);
}
if ((*new_file)->set_ha_share_ref(&p_share_refs->ha_shares[j]))
{
DBUG_RETURN(HA_ERR_OUT_OF_MEM);
}
} while (++j < num_subparts);
if (part_elem->part_state == PART_CHANGED)
orig_count+= num_subparts;
else if (temp_partitions && first)
{
orig_count+= (num_subparts * temp_partitions);
first= FALSE;
}
}
} while (++i < num_parts);
first= FALSE;
/*
Step 5:
Create the new partitions and also open, lock and call external_lock
on them to prepare them for copy phase and also for later close
calls
*/
/*
Before creating new partitions check whether indexes are disabled
in the partitions.
*/
uint disable_non_uniq_indexes = indexes_are_disabled();
i= 0;
part_count= 0;
part_it.rewind();
do
{
partition_element *part_elem= part_it++;
if (part_elem->part_state == PART_TO_BE_ADDED ||
part_elem->part_state == PART_CHANGED)
{
/*
A new partition needs to be created PART_TO_BE_ADDED means an
entirely new partition and PART_CHANGED means a changed partition
that will still exist with either more or less data in it.
*/
uint name_variant= NORMAL_PART_NAME;
if (part_elem->part_state == PART_CHANGED ||
(part_elem->part_state == PART_TO_BE_ADDED && temp_partitions))
name_variant= TEMP_PART_NAME;
if (m_part_info->is_sub_partitioned())
{
List_iterator<partition_element> sub_it(part_elem->subpartitions);
uint j= 0, part;
do
{
partition_element *sub_elem= sub_it++;
if ((error= create_subpartition_name(part_name_buff,
sizeof(part_name_buff), path,
part_elem->partition_name, sub_elem->partition_name,
name_variant)))
{
cleanup_new_partition(part_count);
DBUG_RETURN(error);
}
part= i * num_subparts + j;
DBUG_PRINT("info", ("Add subpartition %s", part_name_buff));
if ((error= prepare_new_partition(table, create_info,
new_file_array[part],
(const char *)part_name_buff,
sub_elem,
disable_non_uniq_indexes)))
{
cleanup_new_partition(part_count);
DBUG_RETURN(error);
}
m_added_file[part_count++]= new_file_array[part];
} while (++j < num_subparts);
}
else
{
if ((error= create_partition_name(part_name_buff,
sizeof(part_name_buff), path, part_elem->partition_name,
name_variant, TRUE)))
{
cleanup_new_partition(part_count);
DBUG_RETURN(error);
}
DBUG_PRINT("info", ("Add partition %s", part_name_buff));
if ((error= prepare_new_partition(table, create_info,
new_file_array[i],
(const char *)part_name_buff,
part_elem,
disable_non_uniq_indexes)))
{
cleanup_new_partition(part_count);
DBUG_RETURN(error);
}
m_added_file[part_count++]= new_file_array[i];
}
}
} while (++i < num_parts);
/*
Step 6:
State update to prepare for next write of the frm file.
*/
i= 0;
part_it.rewind();
do
{
partition_element *part_elem= part_it++;
if (part_elem->part_state == PART_TO_BE_ADDED)
part_elem->part_state= PART_IS_ADDED;
else if (part_elem->part_state == PART_CHANGED)
part_elem->part_state= PART_IS_CHANGED;
else if (part_elem->part_state == PART_REORGED_DROPPED)
part_elem->part_state= PART_TO_BE_DROPPED;
} while (++i < num_parts);
for (i= 0; i < temp_partitions; i++)
{
partition_element *part_elem= t_it++;
DBUG_ASSERT(part_elem->part_state == PART_TO_BE_REORGED);
part_elem->part_state= PART_TO_BE_DROPPED;
}
m_new_file= new_file_array;
if ((error= copy_partitions(copied, deleted)))
{
/*
Close and unlock the new temporary partitions.
They will later be deleted through the ddl-log.
*/
cleanup_new_partition(part_count);
}
DBUG_RETURN(error);
}
/*
Copy partitions as part of ALTER TABLE of partitions
SYNOPSIS
copy_partitions()
out:copied Number of records copied
out:deleted Number of records deleted
RETURN VALUE
>0 Error code
0 Success
DESCRIPTION
change_partitions has done all the preparations, now it is time to
actually copy the data from the reorganised partitions to the new
partitions.
*/
int ha_partition::copy_partitions(ulonglong * const copied,
ulonglong * const deleted)
{
uint reorg_part= 0;
int result= 0;
longlong func_value;
DBUG_ENTER("ha_partition::copy_partitions");
if (m_part_info->linear_hash_ind)
{
if (m_part_info->part_type == HASH_PARTITION)
set_linear_hash_mask(m_part_info, m_part_info->num_parts);
else
set_linear_hash_mask(m_part_info, m_part_info->num_subparts);
}
while (reorg_part < m_reorged_parts)
{
handler *file= m_reorged_file[reorg_part];
uint32 new_part;
late_extra_cache(reorg_part);
if ((result= file->ha_rnd_init_with_error(1)))
goto init_error;
while (TRUE)
{
if ((result= file->ha_rnd_next(m_rec0)))
{
if (result == HA_ERR_RECORD_DELETED)
continue; //Probably MyISAM
if (result != HA_ERR_END_OF_FILE)
goto error;
/*
End-of-file reached, break out to continue with next partition or
end the copy process.
*/
break;
}
/* Found record to insert into new handler */
if (m_part_info->get_partition_id(m_part_info, &new_part,
&func_value))
{
/*
This record is in the original table but will not be in the new
table since it doesn't fit into any partition any longer due to
changed partitioning ranges or list values.
*/
(*deleted)++;
}
else
{
THD *thd= ha_thd();
/* Copy record to new handler */
(*copied)++;
tmp_disable_binlog(thd); /* Do not replicate the low-level changes. */
result= m_new_file[new_part]->ha_write_row(m_rec0);
reenable_binlog(thd);
if (result)
goto error;
}
}
late_extra_no_cache(reorg_part);
file->ha_rnd_end();
reorg_part++;
}
DBUG_RETURN(FALSE);
error:
m_reorged_file[reorg_part]->ha_rnd_end();
init_error:
DBUG_RETURN(result);
}
/*
Update create info as part of ALTER TABLE
SYNOPSIS
update_create_info()
create_info Create info from ALTER TABLE
RETURN VALUE
NONE
DESCRIPTION
Forward this handler call to the storage engine foreach
partition handler. The data_file_name for each partition may
need to be reset if the tablespace was moved. Use a dummy
HA_CREATE_INFO structure and transfer necessary data.
*/
void ha_partition::update_create_info(HA_CREATE_INFO *create_info)
{
DBUG_ENTER("ha_partition::update_create_info");
/*
Fix for bug#38751, some engines needs info-calls in ALTER.
Archive need this since it flushes in ::info.
HA_STATUS_AUTO is optimized so it will not always be forwarded
to all partitions, but HA_STATUS_VARIABLE will.
*/
info(HA_STATUS_VARIABLE);
info(HA_STATUS_AUTO);
if (!(create_info->used_fields & HA_CREATE_USED_AUTO))
create_info->auto_increment_value= stats.auto_increment_value;
/*
DATA DIRECTORY and INDEX DIRECTORY are never applied to the whole
partitioned table, only its parts.
*/
my_bool from_alter = (create_info->data_file_name == (const char*) -1);
create_info->data_file_name= create_info->index_file_name = NULL;
create_info->connect_string= null_lex_str;
/*
We do not need to update the individual partition DATA DIRECTORY settings
since they can be changed by ALTER TABLE ... REORGANIZE PARTITIONS.
*/
if (from_alter)
DBUG_VOID_RETURN;
/*
send Handler::update_create_info() to the storage engine for each
partition that currently has a handler object. Using a dummy
HA_CREATE_INFO structure to collect DATA and INDEX DIRECTORYs.
*/
List_iterator<partition_element> part_it(m_part_info->partitions);
partition_element *part_elem, *sub_elem;
uint num_subparts= m_part_info->num_subparts;
uint num_parts = num_subparts ? m_file_tot_parts / num_subparts
: m_file_tot_parts;
HA_CREATE_INFO dummy_info;
memset(&dummy_info, 0, sizeof(dummy_info));
/*
Since update_create_info() can be called from mysql_prepare_alter_table()
when not all handlers are set up, we look for that condition first.
If all handlers are not available, do not call update_create_info for any.
*/
uint i, j, part;
for (i= 0; i < num_parts; i++)
{
part_elem= part_it++;
if (!part_elem)
DBUG_VOID_RETURN;
if (m_is_sub_partitioned)
{
List_iterator<partition_element> subpart_it(part_elem->subpartitions);
for (j= 0; j < num_subparts; j++)
{
sub_elem= subpart_it++;
if (!sub_elem)
DBUG_VOID_RETURN;
part= i * num_subparts + j;
if (part >= m_file_tot_parts || !m_file[part])
DBUG_VOID_RETURN;
}
}
else
{
if (!m_file[i])
DBUG_VOID_RETURN;
}
}
part_it.rewind();
for (i= 0; i < num_parts; i++)
{
part_elem= part_it++;
DBUG_ASSERT(part_elem);
if (m_is_sub_partitioned)
{
List_iterator<partition_element> subpart_it(part_elem->subpartitions);
for (j= 0; j < num_subparts; j++)
{
sub_elem= subpart_it++;
DBUG_ASSERT(sub_elem);
part= i * num_subparts + j;
DBUG_ASSERT(part < m_file_tot_parts);
DBUG_ASSERT(m_file[part]);
dummy_info.data_file_name= dummy_info.index_file_name = NULL;
m_file[part]->update_create_info(&dummy_info);
sub_elem->data_file_name = (char*) dummy_info.data_file_name;
sub_elem->index_file_name = (char*) dummy_info.index_file_name;
}
}
else
{
DBUG_ASSERT(m_file[i]);
dummy_info.data_file_name= dummy_info.index_file_name= NULL;
m_file[i]->update_create_info(&dummy_info);
part_elem->data_file_name = (char*) dummy_info.data_file_name;
part_elem->index_file_name = (char*) dummy_info.index_file_name;
}
}
DBUG_VOID_RETURN;
}
/**
Change the internal TABLE_SHARE pointer
@param table_arg TABLE object
@param share New share to use
@note Is used in error handling in ha_delete_table.
All handlers should exist (lock_partitions should not be used)
*/
void ha_partition::change_table_ptr(TABLE *table_arg, TABLE_SHARE *share)
{
handler **file_array;
table= table_arg;
table_share= share;
/*
m_file can be NULL when using an old cached table in DROP TABLE, when the
table just has REMOVED PARTITIONING, see Bug#42438
*/
if (m_file)
{
file_array= m_file;
DBUG_ASSERT(*file_array);
do
{
(*file_array)->change_table_ptr(table_arg, share);
} while (*(++file_array));
}
if (m_added_file && m_added_file[0])
{
/* if in middle of a drop/rename etc */
file_array= m_added_file;
do
{
(*file_array)->change_table_ptr(table_arg, share);
} while (*(++file_array));
}
}
/**
Handle delete and rename table
@param from Full path of old table
@param to Full path of new table
@return Operation status
@retval >0 Error
@retval 0 Success
@note Common routine to handle delete_table and rename_table.
The routine uses the partition handler file to get the
names of the partition instances. Both these routines
are called after creating the handler without table
object and thus the file is needed to discover the
names of the partitions and the underlying storage engines.
*/
uint ha_partition::del_ren_table(const char *from, const char *to)
{
int save_error= 0;
int error;
char from_buff[FN_REFLEN + 1], to_buff[FN_REFLEN + 1],
from_lc_buff[FN_REFLEN], to_lc_buff[FN_REFLEN];
char *name_buffer_ptr;
const char *from_path;
const char *to_path= NULL;
uint i;
handler **file, **abort_file;
DBUG_ENTER("ha_partition::del_ren_table");
if (get_from_handler_file(from, ha_thd()->mem_root, false))
DBUG_RETURN(TRUE);
DBUG_ASSERT(m_file_buffer);
DBUG_PRINT("enter", ("from: (%s) to: (%s)", from, to ? to : "(nil)"));
name_buffer_ptr= m_name_buffer_ptr;
file= m_file;
if (to == NULL)
{
/*
Delete table, start by delete the .par file. If error, break, otherwise
delete as much as possible.
*/
if ((error= handler::delete_table(from)))
DBUG_RETURN(error);
}
/*
Since ha_partition has HA_FILE_BASED, it must alter underlying table names
if they do not have HA_FILE_BASED and lower_case_table_names == 2.
See Bug#37402, for Mac OS X.
The appended #P#<partname>[#SP#<subpartname>] will remain in current case.
Using the first partitions handler, since mixing handlers is not allowed.
*/
from_path= get_canonical_filename(*file, from, from_lc_buff);
if (to != NULL)
to_path= get_canonical_filename(*file, to, to_lc_buff);
i= 0;
do
{
if ((error= create_partition_name(from_buff, sizeof(from_buff), from_path,
name_buffer_ptr, NORMAL_PART_NAME, FALSE)))
goto rename_error;
if (to != NULL)
{ // Rename branch
if ((error= create_partition_name(to_buff, sizeof(to_buff), to_path,
name_buffer_ptr, NORMAL_PART_NAME, FALSE)))
goto rename_error;
error= (*file)->ha_rename_table(from_buff, to_buff);
if (error)
goto rename_error;
}
else // delete branch
{
error= (*file)->ha_delete_table(from_buff);
}
name_buffer_ptr= strend(name_buffer_ptr) + 1;
if (error)
save_error= error;
i++;
} while (*(++file));
if (to != NULL)
{
if ((error= handler::rename_table(from, to)))
{
/* Try to revert everything, ignore errors */
(void) handler::rename_table(to, from);
goto rename_error;
}
}
DBUG_RETURN(save_error);
rename_error:
name_buffer_ptr= m_name_buffer_ptr;
for (abort_file= file, file= m_file; file < abort_file; file++)
{
/* Revert the rename, back from 'to' to the original 'from' */
if (!create_partition_name(from_buff, sizeof(from_buff), from_path,
name_buffer_ptr, NORMAL_PART_NAME, FALSE) &&
!create_partition_name(to_buff, sizeof(to_buff), to_path,
name_buffer_ptr, NORMAL_PART_NAME, FALSE))
{
/* Ignore error here */
(void) (*file)->ha_rename_table(to_buff, from_buff);
}
name_buffer_ptr= strend(name_buffer_ptr) + 1;
}
DBUG_RETURN(error);
}
uint ha_partition::count_query_cache_dependant_tables(uint8 *tables_type)
{
DBUG_ENTER("ha_partition::count_query_cache_dependant_tables");
/* Here we rely on the fact that all tables are of the same type */
uint8 type= m_file[0]->table_cache_type();
(*tables_type)|= type;
DBUG_PRINT("info", ("cnt: %u", (uint)m_tot_parts));
/*
We need save underlying tables only for HA_CACHE_TBL_ASKTRANSACT:
HA_CACHE_TBL_NONTRANSACT - because all changes goes through partition table
HA_CACHE_TBL_NOCACHE - because will not be cached
HA_CACHE_TBL_TRANSACT - QC need to know that such type present
*/
DBUG_RETURN(type == HA_CACHE_TBL_ASKTRANSACT ? m_tot_parts : 0);
}
my_bool ha_partition::
reg_query_cache_dependant_table(THD *thd,
char *engine_key, uint engine_key_len,
char *cache_key, uint cache_key_len,
uint8 type,
Query_cache *cache,
Query_cache_block_table **block_table,
handler *file,
uint *n)
{
DBUG_ENTER("ha_partition::reg_query_cache_dependant_table");
qc_engine_callback engine_callback;
ulonglong engine_data;
/* ask undelying engine */
if (!file->register_query_cache_table(thd, engine_key,
engine_key_len,
&engine_callback,
&engine_data))
{
DBUG_PRINT("qcache", ("Handler does not allow caching for %.*s",
engine_key_len, engine_key));
/*
As this can change from call to call, don't reset set
thd->lex->safe_to_cache_query
*/
thd->query_cache_is_applicable= 0; // Query can't be cached
DBUG_RETURN(TRUE);
}
(++(*block_table))->n= ++(*n);
if (!cache->insert_table(thd, cache_key_len,
cache_key, (*block_table),
table_share->db.length,
(uint8) (cache_key_len -
table_share->table_cache_key.length),
type,
engine_callback, engine_data,
FALSE))
DBUG_RETURN(TRUE);
DBUG_RETURN(FALSE);
}
my_bool ha_partition::
register_query_cache_dependant_tables(THD *thd,
Query_cache *cache,
Query_cache_block_table **block_table,
uint *n)
{
char *engine_key_end, *query_cache_key_end;
uint i;
uint num_parts= m_part_info->num_parts;
uint num_subparts= m_part_info->num_subparts;
int diff_length;
List_iterator<partition_element> part_it(m_part_info->partitions);
char engine_key[FN_REFLEN], query_cache_key[FN_REFLEN];
DBUG_ENTER("ha_partition::register_query_cache_dependant_tables");
/* see ha_partition::count_query_cache_dependant_tables */
if (m_file[0]->table_cache_type() != HA_CACHE_TBL_ASKTRANSACT)
DBUG_RETURN(FALSE); // nothing to register
/* prepare static part of the key */
memcpy(engine_key, table_share->normalized_path.str,
table_share->normalized_path.length);
memcpy(query_cache_key, table_share->table_cache_key.str,
table_share->table_cache_key.length);
diff_length= ((int) table_share->table_cache_key.length -
(int) table_share->normalized_path.length -1);
engine_key_end= engine_key + table_share->normalized_path.length;
query_cache_key_end= query_cache_key + table_share->table_cache_key.length -1;
engine_key_end[0]= engine_key_end[2]= query_cache_key_end[0]=
query_cache_key_end[2]= '#';
query_cache_key_end[1]= engine_key_end[1]= 'P';
engine_key_end+= 3;
query_cache_key_end+= 3;
i= 0;
do
{
partition_element *part_elem= part_it++;
char *engine_pos= strmov(engine_key_end, part_elem->partition_name);
if (m_is_sub_partitioned)
{
List_iterator<partition_element> subpart_it(part_elem->subpartitions);
partition_element *sub_elem;
uint j= 0, part;
engine_pos[0]= engine_pos[3]= '#';
engine_pos[1]= 'S';
engine_pos[2]= 'P';
engine_pos += 4;
do
{
char *end;
uint length;
sub_elem= subpart_it++;
part= i * num_subparts + j;
/* we store the end \0 as part of the key */
end= strmov(engine_pos, sub_elem->partition_name);
length= (uint)(end - engine_key);
/* Copy the suffix also to query cache key */
memcpy(query_cache_key_end, engine_key_end, (end - engine_key_end));
if (reg_query_cache_dependant_table(thd, engine_key, length,
query_cache_key,
length + diff_length,
m_file[part]->table_cache_type(),
cache,
block_table, m_file[part],
n))
DBUG_RETURN(TRUE);
} while (++j < num_subparts);
}
else
{
char *end= engine_pos+1; // copy end \0
uint length= (uint)(end - engine_key);
/* Copy the suffix also to query cache key */
memcpy(query_cache_key_end, engine_key_end, (end - engine_key_end));
if (reg_query_cache_dependant_table(thd, engine_key, length,
query_cache_key,
length + diff_length,
m_file[i]->table_cache_type(),
cache,
block_table, m_file[i],
n))
DBUG_RETURN(TRUE);
}
} while (++i < num_parts);
DBUG_PRINT("info", ("cnt: %u", (uint)m_tot_parts));
DBUG_RETURN(FALSE);
}
/**
Set up table share object before calling create on underlying handler
@param table Table object
@param info Create info
@param part_elem[in,out] Pointer to used partition_element, searched if NULL
@return status
@retval TRUE Error
@retval FALSE Success
@details
Set up
1) Comment on partition
2) MAX_ROWS, MIN_ROWS on partition
3) Index file name on partition
4) Data file name on partition
*/
int ha_partition::set_up_table_before_create(TABLE *tbl,
const char *partition_name_with_path,
HA_CREATE_INFO *info,
partition_element *part_elem)
{
int error= 0;
const char *partition_name;
THD *thd= ha_thd();
DBUG_ENTER("set_up_table_before_create");
DBUG_ASSERT(part_elem);
if (!part_elem)
DBUG_RETURN(1);
tbl->s->max_rows= part_elem->part_max_rows;
tbl->s->min_rows= part_elem->part_min_rows;
partition_name= strrchr(partition_name_with_path, FN_LIBCHAR);
if ((part_elem->index_file_name &&
(error= append_file_to_dir(thd,
(const char**)&part_elem->index_file_name,
partition_name+1))) ||
(part_elem->data_file_name &&
(error= append_file_to_dir(thd,
(const char**)&part_elem->data_file_name,
partition_name+1))))
{
DBUG_RETURN(error);
}
info->index_file_name= part_elem->index_file_name;
info->data_file_name= part_elem->data_file_name;
info->connect_string= part_elem->connect_string;
if (info->connect_string.length)
info->used_fields|= HA_CREATE_USED_CONNECTION;
tbl->s->connect_string= part_elem->connect_string;
DBUG_RETURN(0);
}
/*
Add two names together
SYNOPSIS
name_add()
out:dest Destination string
first_name First name
sec_name Second name
RETURN VALUE
>0 Error
0 Success
DESCRIPTION
Routine used to add two names with '_' in between then. Service routine
to create_handler_file
Include the NULL in the count of characters since it is needed as separator
between the partition names.
*/
static uint name_add(char *dest, const char *first_name, const char *sec_name)
{
return (uint) (strxmov(dest, first_name, "#SP#", sec_name, NullS) -dest) + 1;
}
/**
Create the special .par file
@param name Full path of table name
@return Operation status
@retval FALSE Error code
@retval TRUE Success
@note
Method used to create handler file with names of partitions, their
engine types and the number of partitions.
*/
bool ha_partition::create_handler_file(const char *name)
{
partition_element *part_elem, *subpart_elem;
uint i, j, part_name_len, subpart_name_len;
uint tot_partition_words, tot_name_len, num_parts;
uint tot_parts= 0;
uint tot_len_words, tot_len_byte, chksum, tot_name_words;
char *name_buffer_ptr;
uchar *file_buffer, *engine_array;
bool result= TRUE;
char file_name[FN_REFLEN];
char part_name[FN_REFLEN];
char subpart_name[FN_REFLEN];
File file;
List_iterator_fast <partition_element> part_it(m_part_info->partitions);
DBUG_ENTER("create_handler_file");
num_parts= m_part_info->partitions.elements;
DBUG_PRINT("info", ("table name = %s, num_parts = %u", name,
num_parts));
tot_name_len= 0;
for (i= 0; i < num_parts; i++)
{
part_elem= part_it++;
if (part_elem->part_state != PART_NORMAL &&
part_elem->part_state != PART_TO_BE_ADDED &&
part_elem->part_state != PART_CHANGED)
continue;
tablename_to_filename(part_elem->partition_name, part_name,
FN_REFLEN);
part_name_len= strlen(part_name);
if (!m_is_sub_partitioned)
{
tot_name_len+= part_name_len + 1;
tot_parts++;
}
else
{
List_iterator_fast <partition_element> sub_it(part_elem->subpartitions);
for (j= 0; j < m_part_info->num_subparts; j++)
{
subpart_elem= sub_it++;
tablename_to_filename(subpart_elem->partition_name,
subpart_name,
FN_REFLEN);
subpart_name_len= strlen(subpart_name);
tot_name_len+= part_name_len + subpart_name_len + 5;
tot_parts++;
}
}
}
/*
File format:
Length in words 4 byte
Checksum 4 byte
Total number of partitions 4 byte
Array of engine types n * 4 bytes where
n = (m_tot_parts + 3)/4
Length of name part in bytes 4 bytes
(Names in filename format)
Name part m * 4 bytes where
m = ((length_name_part + 3)/4)*4
All padding bytes are zeroed
*/
tot_partition_words= (tot_parts + PAR_WORD_SIZE - 1) / PAR_WORD_SIZE;
tot_name_words= (tot_name_len + PAR_WORD_SIZE - 1) / PAR_WORD_SIZE;
/* 4 static words (tot words, checksum, tot partitions, name length) */
tot_len_words= 4 + tot_partition_words + tot_name_words;
tot_len_byte= PAR_WORD_SIZE * tot_len_words;
if (!(file_buffer= (uchar *) my_malloc(tot_len_byte, MYF(MY_ZEROFILL))))
DBUG_RETURN(TRUE);
engine_array= (file_buffer + PAR_ENGINES_OFFSET);
name_buffer_ptr= (char*) (engine_array + tot_partition_words * PAR_WORD_SIZE
+ PAR_WORD_SIZE);
part_it.rewind();
for (i= 0; i < num_parts; i++)
{
part_elem= part_it++;
if (part_elem->part_state != PART_NORMAL &&
part_elem->part_state != PART_TO_BE_ADDED &&
part_elem->part_state != PART_CHANGED)
continue;
if (!m_is_sub_partitioned)
{
tablename_to_filename(part_elem->partition_name, part_name, FN_REFLEN);
name_buffer_ptr= strmov(name_buffer_ptr, part_name)+1;
*engine_array= (uchar) ha_legacy_type(part_elem->engine_type);
DBUG_PRINT("info", ("engine: %u", *engine_array));
engine_array++;
}
else
{
List_iterator_fast <partition_element> sub_it(part_elem->subpartitions);
for (j= 0; j < m_part_info->num_subparts; j++)
{
subpart_elem= sub_it++;
tablename_to_filename(part_elem->partition_name, part_name,
FN_REFLEN);
tablename_to_filename(subpart_elem->partition_name, subpart_name,
FN_REFLEN);
name_buffer_ptr+= name_add(name_buffer_ptr,
part_name,
subpart_name);
*engine_array= (uchar) ha_legacy_type(subpart_elem->engine_type);
DBUG_PRINT("info", ("engine: %u", *engine_array));
engine_array++;
}
}
}
chksum= 0;
int4store(file_buffer, tot_len_words);
int4store(file_buffer + PAR_NUM_PARTS_OFFSET, tot_parts);
int4store(file_buffer + PAR_ENGINES_OFFSET +
(tot_partition_words * PAR_WORD_SIZE),
tot_name_len);
for (i= 0; i < tot_len_words; i++)
chksum^= uint4korr(file_buffer + PAR_WORD_SIZE * i);
int4store(file_buffer + PAR_CHECKSUM_OFFSET, chksum);
/*
Add .par extension to the file name.
Create and write and close file
to be used at open, delete_table and rename_table
*/
fn_format(file_name, name, "", ha_par_ext, MY_APPEND_EXT);
if ((file= mysql_file_create(key_file_partition,
file_name, CREATE_MODE, O_RDWR | O_TRUNC,
MYF(MY_WME))) >= 0)
{
result= mysql_file_write(file, (uchar *) file_buffer, tot_len_byte,
MYF(MY_WME | MY_NABP)) != 0;
/* Write connection information (for federatedx engine) */
part_it.rewind();
for (i= 0; i < num_parts && !result; i++)
{
uchar buffer[4];
part_elem= part_it++;
uint length = part_elem->connect_string.length;
int4store(buffer, length);
if (my_write(file, buffer, 4, MYF(MY_WME | MY_NABP)) ||
my_write(file, (uchar *) part_elem->connect_string.str, length,
MYF(MY_WME | MY_NABP)))
{
result= TRUE;
break;
}
}
(void) mysql_file_close(file, MYF(0));
}
else
result= TRUE;
my_free(file_buffer);
DBUG_RETURN(result);
}
/**
Clear handler variables and free some memory
*/
void ha_partition::clear_handler_file()
{
if (m_engine_array)
plugin_unlock_list(NULL, m_engine_array, m_tot_parts);
free_root(&m_mem_root, MYF(MY_KEEP_PREALLOC));
m_file_buffer= NULL;
m_engine_array= NULL;
m_connect_string= NULL;
}
/**
Create underlying handler objects
@param mem_root Allocate memory through this
@return Operation status
@retval TRUE Error
@retval FALSE Success
*/
bool ha_partition::create_handlers(MEM_ROOT *mem_root)
{
uint i;
uint alloc_len= (m_tot_parts + 1) * sizeof(handler*);
handlerton *hton0;
DBUG_ENTER("create_handlers");
if (!(m_file= (handler **) alloc_root(mem_root, alloc_len)))
DBUG_RETURN(TRUE);
m_file_tot_parts= m_tot_parts;
bzero((char*) m_file, alloc_len);
for (i= 0; i < m_tot_parts; i++)
{
handlerton *hton= plugin_data(m_engine_array[i], handlerton*);
if (!(m_file[i]= get_new_handler(table_share, mem_root, hton)))
DBUG_RETURN(TRUE);
DBUG_PRINT("info", ("engine_type: %u", hton->db_type));
}
/* For the moment we only support partition over the same table engine */
hton0= plugin_data(m_engine_array[0], handlerton*);
if (hton0 == myisam_hton)
{
DBUG_PRINT("info", ("MyISAM"));
m_myisam= TRUE;
}
/* INNODB may not be compiled in... */
else if (ha_legacy_type(hton0) == DB_TYPE_INNODB)
{
DBUG_PRINT("info", ("InnoDB"));
m_innodb= TRUE;
}
DBUG_RETURN(FALSE);
}
/*
Create underlying handler objects from partition info
SYNOPSIS
new_handlers_from_part_info()
mem_root Allocate memory through this
RETURN VALUE
TRUE Error
FALSE Success
*/
bool ha_partition::new_handlers_from_part_info(MEM_ROOT *mem_root)
{
uint i, j, part_count;
partition_element *part_elem;
uint alloc_len= (m_tot_parts + 1) * sizeof(handler*);
List_iterator_fast <partition_element> part_it(m_part_info->partitions);
DBUG_ENTER("ha_partition::new_handlers_from_part_info");
if (!(m_file= (handler **) alloc_root(mem_root, alloc_len)))
{
mem_alloc_error(alloc_len);
goto error_end;
}
m_file_tot_parts= m_tot_parts;
bzero((char*) m_file, alloc_len);
DBUG_ASSERT(m_part_info->num_parts > 0);
i= 0;
part_count= 0;
/*
Don't know the size of the underlying storage engine, invent a number of
bytes allocated for error message if allocation fails
*/
do
{
part_elem= part_it++;
if (m_is_sub_partitioned)
{
for (j= 0; j < m_part_info->num_subparts; j++)
{
if (!(m_file[part_count++]= get_new_handler(table_share, mem_root,
part_elem->engine_type)))
goto error;
DBUG_PRINT("info", ("engine_type: %u",
(uint) ha_legacy_type(part_elem->engine_type)));
}
}
else
{
if (!(m_file[part_count++]= get_new_handler(table_share, mem_root,
part_elem->engine_type)))
goto error;
DBUG_PRINT("info", ("engine_type: %u",
(uint) ha_legacy_type(part_elem->engine_type)));
}
} while (++i < m_part_info->num_parts);
if (part_elem->engine_type == myisam_hton)
{
DBUG_PRINT("info", ("MyISAM"));
m_myisam= TRUE;
}
DBUG_RETURN(FALSE);
error:
mem_alloc_error(sizeof(handler));
error_end:
DBUG_RETURN(TRUE);
}
/**
Read the .par file to get the partitions engines and names
@param name Name of table file (without extension)
@return Operation status
@retval true Failure
@retval false Success
@note On success, m_file_buffer is allocated and must be
freed by the caller. m_name_buffer_ptr and m_tot_parts is also set.
*/
bool ha_partition::read_par_file(const char *name)
{
char buff[FN_REFLEN];
uchar *tot_name_len_offset;
File file;
uchar *file_buffer;
uint i, len_bytes, len_words, tot_partition_words, tot_name_words, chksum;
DBUG_ENTER("ha_partition::read_par_file");
DBUG_PRINT("enter", ("table name: '%s'", name));
if (m_file_buffer)
DBUG_RETURN(false);
fn_format(buff, name, "", ha_par_ext, MY_APPEND_EXT);
/* Following could be done with mysql_file_stat to read in whole file */
if ((file= mysql_file_open(key_file_partition,
buff, O_RDONLY | O_SHARE, MYF(0))) < 0)
DBUG_RETURN(TRUE);
if (mysql_file_read(file, (uchar *) &buff[0], PAR_WORD_SIZE, MYF(MY_NABP)))
goto err1;
len_words= uint4korr(buff);
len_bytes= PAR_WORD_SIZE * len_words;
if (mysql_file_seek(file, 0, MY_SEEK_SET, MYF(0)) == MY_FILEPOS_ERROR)
goto err1;
if (!(file_buffer= (uchar*) alloc_root(&m_mem_root, len_bytes)))
goto err1;
if (mysql_file_read(file, file_buffer, len_bytes, MYF(MY_NABP)))
goto err2;
chksum= 0;
for (i= 0; i < len_words; i++)
chksum ^= uint4korr((file_buffer) + PAR_WORD_SIZE * i);
if (chksum)
goto err2;
m_tot_parts= uint4korr((file_buffer) + PAR_NUM_PARTS_OFFSET);
DBUG_PRINT("info", ("No of parts = %u", m_tot_parts));
tot_partition_words= (m_tot_parts + PAR_WORD_SIZE - 1) / PAR_WORD_SIZE;
tot_name_len_offset= file_buffer + PAR_ENGINES_OFFSET +
PAR_WORD_SIZE * tot_partition_words;
tot_name_words= (uint4korr(tot_name_len_offset) + PAR_WORD_SIZE - 1) /
PAR_WORD_SIZE;
/*
Verify the total length = tot size word, checksum word, num parts word +
engines array + name length word + name array.
*/
if (len_words != (tot_partition_words + tot_name_words + 4))
goto err2;
m_file_buffer= file_buffer; // Will be freed in clear_handler_file()
m_name_buffer_ptr= (char*) (tot_name_len_offset + PAR_WORD_SIZE);
if (!(m_connect_string= (LEX_STRING*)
alloc_root(&m_mem_root, m_tot_parts * sizeof(LEX_STRING))))
goto err2;
bzero(m_connect_string, m_tot_parts * sizeof(LEX_STRING));
/* Read connection arguments (for federated X engine) */
for (i= 0; i < m_tot_parts; i++)
{
LEX_STRING connect_string;
uchar buffer[4];
if (my_read(file, buffer, 4, MYF(MY_NABP)))
{
/* No extra options; Probably not a federatedx engine */
break;
}
connect_string.length= uint4korr(buffer);
connect_string.str= (char*) alloc_root(&m_mem_root, connect_string.length+1);
if (my_read(file, (uchar*) connect_string.str, connect_string.length,
MYF(MY_NABP)))
break;
connect_string.str[connect_string.length]= 0;
m_connect_string[i]= connect_string;
}
(void) mysql_file_close(file, MYF(0));
DBUG_RETURN(false);
err2:
err1:
(void) mysql_file_close(file, MYF(0));
DBUG_RETURN(true);
}
/**
Setup m_engine_array
@param mem_root MEM_ROOT to use for allocating new handlers
@return Operation status
@retval false Success
@retval true Failure
*/
bool ha_partition::setup_engine_array(MEM_ROOT *mem_root)
{
uint i;
uchar *buff;
handlerton **engine_array, *first_engine;
enum legacy_db_type db_type, first_db_type;
DBUG_ASSERT(!m_file);
DBUG_ENTER("ha_partition::setup_engine_array");
engine_array= (handlerton **) my_alloca(m_tot_parts * sizeof(handlerton*));
if (!engine_array)
DBUG_RETURN(true);
buff= (uchar *) (m_file_buffer + PAR_ENGINES_OFFSET);
first_db_type= (enum legacy_db_type) buff[0];
first_engine= ha_resolve_by_legacy_type(ha_thd(), first_db_type);
if (!first_engine)
goto err;
if (!(m_engine_array= (plugin_ref*)
alloc_root(&m_mem_root, m_tot_parts * sizeof(plugin_ref))))
goto err;
for (i= 0; i < m_tot_parts; i++)
{
db_type= (enum legacy_db_type) buff[i];
if (db_type != first_db_type)
{
DBUG_PRINT("error", ("partition %u engine %d is not same as "
"first partition %d", i, db_type,
(int) first_db_type));
DBUG_ASSERT(0);
clear_handler_file();
goto err;
}
m_engine_array[i]= ha_lock_engine(NULL, first_engine);
if (!m_engine_array[i])
{
clear_handler_file();
goto err;
}
}
my_afree(engine_array);
if (create_handlers(mem_root))
{
clear_handler_file();
DBUG_RETURN(true);
}
DBUG_RETURN(false);
err:
my_afree(engine_array);
DBUG_RETURN(true);
}
/**
Get info about partition engines and their names from the .par file
@param name Full path of table name
@param mem_root Allocate memory through this
@param is_clone If it is a clone, don't create new handlers
@return Operation status
@retval true Error
@retval false Success
@note Open handler file to get partition names, engine types and number of
partitions.
*/
bool ha_partition::get_from_handler_file(const char *name, MEM_ROOT *mem_root,
bool is_clone)
{
DBUG_ENTER("ha_partition::get_from_handler_file");
DBUG_PRINT("enter", ("table name: '%s'", name));
if (m_file_buffer)
DBUG_RETURN(false);
if (read_par_file(name))
DBUG_RETURN(true);
if (!is_clone && setup_engine_array(mem_root))
DBUG_RETURN(true);
DBUG_RETURN(false);
}
/****************************************************************************
MODULE open/close object
****************************************************************************/
/**
Get the partition name.
@param part Struct containing name and length
@param[out] length Length of the name
@return Partition name
*/
static uchar *get_part_name(PART_NAME_DEF *part, size_t *length,
my_bool not_used __attribute__((unused)))
{
*length= part->length;
return part->partition_name;
}
/**
Insert a partition name in the partition_name_hash.
@param name Name of partition
@param part_id Partition id (number)
@param is_subpart Set if the name belongs to a subpartition
@return Operation status
@retval true Failure
@retval false Success
*/
bool ha_partition::insert_partition_name_in_hash(const char *name, uint part_id,
bool is_subpart)
{
PART_NAME_DEF *part_def;
uchar *part_name;
uint part_name_length;
DBUG_ENTER("ha_partition::insert_partition_name_in_hash");
/*
Calculate and store the length here, to avoid doing it when
searching the hash.
*/
part_name_length= strlen(name);
/*
Must use memory that lives as long as table_share.
Freed in the Partition_share destructor.
Since we use my_multi_malloc, then my_free(part_def) will also free
part_name, as a part of my_hash_free.
*/
if (!my_multi_malloc(MY_WME,
&part_def, sizeof(PART_NAME_DEF),
&part_name, part_name_length + 1,
NULL))
DBUG_RETURN(true);
memcpy(part_name, name, part_name_length + 1);
part_def->partition_name= part_name;
part_def->length= part_name_length;
part_def->part_id= part_id;
part_def->is_subpart= is_subpart;
if (my_hash_insert(&part_share->partition_name_hash, (uchar *) part_def))
{
my_free(part_def);
DBUG_RETURN(true);
}
DBUG_RETURN(false);
}
/**
Populate the partition_name_hash in part_share.
*/
bool ha_partition::populate_partition_name_hash()
{
List_iterator<partition_element> part_it(m_part_info->partitions);
uint num_parts= m_part_info->num_parts;
uint num_subparts= m_is_sub_partitioned ? m_part_info->num_subparts : 1;
uint tot_names;
uint i= 0;
DBUG_ASSERT(part_share);
DBUG_ENTER("ha_partition::populate_partition_name_hash");
/*
partition_name_hash is only set once and never changed
-> OK to check without locking.
*/
if (part_share->partition_name_hash_initialized)
DBUG_RETURN(false);
lock_shared_ha_data();
if (part_share->partition_name_hash_initialized)
{
unlock_shared_ha_data();
DBUG_RETURN(false);
}
tot_names= m_is_sub_partitioned ? m_tot_parts + num_parts : num_parts;
if (my_hash_init(&part_share->partition_name_hash,
system_charset_info, tot_names, 0, 0,
(my_hash_get_key) get_part_name,
my_free, HASH_UNIQUE))
{
unlock_shared_ha_data();
DBUG_RETURN(TRUE);
}
do
{
partition_element *part_elem= part_it++;
DBUG_ASSERT(part_elem->part_state == PART_NORMAL);
if (part_elem->part_state == PART_NORMAL)
{
if (insert_partition_name_in_hash(part_elem->partition_name,
i * num_subparts, false))
goto err;
if (m_is_sub_partitioned)
{
List_iterator<partition_element>
subpart_it(part_elem->subpartitions);
partition_element *sub_elem;
uint j= 0;
do
{
sub_elem= subpart_it++;
if (insert_partition_name_in_hash(sub_elem->partition_name,
i * num_subparts + j, true))
goto err;
} while (++j < num_subparts);
}
}
} while (++i < num_parts);
part_share->partition_name_hash_initialized= true;
unlock_shared_ha_data();
DBUG_RETURN(FALSE);
err:
my_hash_free(&part_share->partition_name_hash);
unlock_shared_ha_data();
DBUG_RETURN(TRUE);
}
/**
Set Handler_share pointer and allocate Handler_share pointers
for each partition and set those.
@param ha_share_arg Where to store/retrieve the Partitioning_share pointer
to be shared by all instances of the same table.
@return Operation status
@retval true Failure
@retval false Success
*/
bool ha_partition::set_ha_share_ref(Handler_share **ha_share_arg)
{
Handler_share **ha_shares;
uint i;
DBUG_ENTER("ha_partition::set_ha_share_ref");
DBUG_ASSERT(!part_share);
DBUG_ASSERT(table_share);
DBUG_ASSERT(!m_is_clone_of);
DBUG_ASSERT(m_tot_parts);
if (handler::set_ha_share_ref(ha_share_arg))
DBUG_RETURN(true);
if (!(part_share= get_share()))
DBUG_RETURN(true);
DBUG_ASSERT(part_share->partitions_share_refs);
DBUG_ASSERT(part_share->partitions_share_refs->num_parts >= m_tot_parts);
ha_shares= part_share->partitions_share_refs->ha_shares;
for (i= 0; i < m_tot_parts; i++)
{
if (m_file[i]->set_ha_share_ref(&ha_shares[i]))
DBUG_RETURN(true);
}
DBUG_RETURN(false);
}
/**
Get the PARTITION_SHARE for the table.
@return Operation status
@retval true Error
@retval false Success
@note Gets or initializes the Partition_share object used by partitioning.
The Partition_share is used for handling the auto_increment etc.
*/
Partition_share *ha_partition::get_share()
{
Partition_share *tmp_share;
DBUG_ENTER("ha_partition::get_share");
DBUG_ASSERT(table_share);
lock_shared_ha_data();
if (!(tmp_share= static_cast<Partition_share*>(get_ha_share_ptr())))
{
tmp_share= new Partition_share;
if (!tmp_share)
goto err;
if (tmp_share->init(m_tot_parts))
{
delete tmp_share;
tmp_share= NULL;
goto err;
}
set_ha_share_ptr(static_cast<Handler_share*>(tmp_share));
}
err:
unlock_shared_ha_data();
DBUG_RETURN(tmp_share);
}
/**
Helper function for freeing all internal bitmaps.
*/
void ha_partition::free_partition_bitmaps()
{
/* Initialize the bitmap we use to minimize ha_start_bulk_insert calls */
my_bitmap_free(&m_bulk_insert_started);
my_bitmap_free(&m_locked_partitions);
my_bitmap_free(&m_partitions_to_reset);
my_bitmap_free(&m_key_not_found_partitions);
}
/**
Helper function for initializing all internal bitmaps.
*/
bool ha_partition::init_partition_bitmaps()
{
DBUG_ENTER("ha_partition::init_partition_bitmaps");
/* Initialize the bitmap we use to minimize ha_start_bulk_insert calls */
if (my_bitmap_init(&m_bulk_insert_started, NULL, m_tot_parts + 1, FALSE))
DBUG_RETURN(true);
bitmap_clear_all(&m_bulk_insert_started);
/* Initialize the bitmap we use to keep track of locked partitions */
if (my_bitmap_init(&m_locked_partitions, NULL, m_tot_parts, FALSE))
{
my_bitmap_free(&m_bulk_insert_started);
DBUG_RETURN(true);
}
bitmap_clear_all(&m_locked_partitions);
/*
Initialize the bitmap we use to keep track of partitions which may have
something to reset in ha_reset().
*/
if (my_bitmap_init(&m_partitions_to_reset, NULL, m_tot_parts, FALSE))
{
my_bitmap_free(&m_bulk_insert_started);
my_bitmap_free(&m_locked_partitions);
DBUG_RETURN(true);
}
bitmap_clear_all(&m_partitions_to_reset);
/*
Initialize the bitmap we use to keep track of partitions which returned
HA_ERR_KEY_NOT_FOUND from index_read_map.
*/
if (my_bitmap_init(&m_key_not_found_partitions, NULL, m_tot_parts, FALSE))
{
my_bitmap_free(&m_bulk_insert_started);
my_bitmap_free(&m_locked_partitions);
my_bitmap_free(&m_partitions_to_reset);
DBUG_RETURN(true);
}
bitmap_clear_all(&m_key_not_found_partitions);
m_key_not_found= false;
/* Initialize the bitmap for read/lock_partitions */
if (!m_is_clone_of)
{
DBUG_ASSERT(!m_clone_mem_root);
if (m_part_info->set_partition_bitmaps(NULL))
{
free_partition_bitmaps();
DBUG_RETURN(true);
}
}
DBUG_RETURN(false);
}
/*
Open handler object
SYNOPSIS
open()
name Full path of table name
mode Open mode flags
test_if_locked ?
RETURN VALUE
>0 Error
0 Success
DESCRIPTION
Used for opening tables. The name will be the name of the file.
A table is opened when it needs to be opened. For instance
when a request comes in for a select on the table (tables are not
open and closed for each request, they are cached).
Called from handler.cc by handler::ha_open(). The server opens all tables
by calling ha_open() which then calls the handler specific open().
*/
int ha_partition::open(const char *name, int mode, uint test_if_locked)
{
char *name_buffer_ptr;
int error= HA_ERR_INITIALIZATION;
handler **file;
char name_buff[FN_REFLEN + 1];
ulonglong check_table_flags;
DBUG_ENTER("ha_partition::open");
DBUG_ASSERT(table->s == table_share);
ref_length= 0;
m_mode= mode;
m_open_test_lock= test_if_locked;
m_part_field_array= m_part_info->full_part_field_array;
if (get_from_handler_file(name, &table->mem_root, MY_TEST(m_is_clone_of)))
DBUG_RETURN(error);
name_buffer_ptr= m_name_buffer_ptr;
if (populate_partition_name_hash())
{
DBUG_RETURN(HA_ERR_INITIALIZATION);
}
m_start_key.length= 0;
m_rec0= table->record[0];
m_rec_length= table_share->reclength;
if (!m_part_ids_sorted_by_num_of_records)
{
if (!(m_part_ids_sorted_by_num_of_records=
(uint32*) my_malloc(m_tot_parts * sizeof(uint32), MYF(MY_WME))))
DBUG_RETURN(error);
uint32 i;
/* Initialize it with all partition ids. */
for (i= 0; i < m_tot_parts; i++)
m_part_ids_sorted_by_num_of_records[i]= i;
}
if (init_partition_bitmaps())
DBUG_RETURN(error);
DBUG_ASSERT(m_part_info);
if (m_is_clone_of)
{
uint i, alloc_len;
DBUG_ASSERT(m_clone_mem_root);
/* Allocate an array of handler pointers for the partitions handlers. */
alloc_len= (m_tot_parts + 1) * sizeof(handler*);
if (!(m_file= (handler **) alloc_root(m_clone_mem_root, alloc_len)))
{
error= HA_ERR_INITIALIZATION;
goto err_alloc;
}
memset(m_file, 0, alloc_len);
/*
Populate them by cloning the original partitions. This also opens them.
Note that file->ref is allocated too.
*/
file= m_is_clone_of->m_file;
for (i= 0; i < m_tot_parts; i++)
{
if ((error= create_partition_name(name_buff, sizeof(name_buff), name,
name_buffer_ptr, NORMAL_PART_NAME, FALSE)))
goto err_handler;
/* ::clone() will also set ha_share from the original. */
if (!(m_file[i]= file[i]->clone(name_buff, m_clone_mem_root)))
{
error= HA_ERR_INITIALIZATION;
file= &m_file[i];
goto err_handler;
}
name_buffer_ptr+= strlen(name_buffer_ptr) + 1;
}
}
else
{
file= m_file;
do
{
if ((error= create_partition_name(name_buff, sizeof(name_buff), name,
name_buffer_ptr, NORMAL_PART_NAME, FALSE)))
goto err_handler;
table->s->connect_string = m_connect_string[(uint)(file-m_file)];
if ((error= (*file)->ha_open(table, name_buff, mode,
test_if_locked | HA_OPEN_NO_PSI_CALL)))
goto err_handler;
bzero(&table->s->connect_string, sizeof(LEX_STRING));
if (m_file == file)
m_num_locks= (*file)->lock_count();
DBUG_ASSERT(m_num_locks == (*file)->lock_count());
name_buffer_ptr+= strlen(name_buffer_ptr) + 1;
} while (*(++file));
}
file= m_file;
ref_length= (*file)->ref_length;
check_table_flags= (((*file)->ha_table_flags() &
~(PARTITION_DISABLED_TABLE_FLAGS)) |
(PARTITION_ENABLED_TABLE_FLAGS));
while (*(++file))
{
/* MyISAM can have smaller ref_length for partitions with MAX_ROWS set */
set_if_bigger(ref_length, ((*file)->ref_length));
/*
Verify that all partitions have the same set of table flags.
Mask all flags that partitioning enables/disables.
*/
if (check_table_flags != (((*file)->ha_table_flags() &
~(PARTITION_DISABLED_TABLE_FLAGS)) |
(PARTITION_ENABLED_TABLE_FLAGS)))
{
error= HA_ERR_INITIALIZATION;
/* set file to last handler, so all of them are closed */
file = &m_file[m_tot_parts - 1];
goto err_handler;
}
}
key_used_on_scan= m_file[0]->key_used_on_scan;
implicit_emptied= m_file[0]->implicit_emptied;
/*
Add 2 bytes for partition id in position ref length.
ref_length=max_in_all_partitions(ref_length) + PARTITION_BYTES_IN_POS
*/
ref_length+= PARTITION_BYTES_IN_POS;
m_ref_length= ref_length;
/*
Release buffer read from .par file. It will not be reused again after
being opened once.
*/
clear_handler_file();
/*
Some handlers update statistics as part of the open call. This will in
some cases corrupt the statistics of the partition handler and thus
to ensure we have correct statistics we call info from open after
calling open on all individual handlers.
*/
m_handler_status= handler_opened;
if (m_part_info->part_expr)
m_part_func_monotonicity_info=
m_part_info->part_expr->get_monotonicity_info();
else if (m_part_info->list_of_part_fields)
m_part_func_monotonicity_info= MONOTONIC_STRICT_INCREASING;
info(HA_STATUS_VARIABLE | HA_STATUS_CONST);
DBUG_RETURN(0);
err_handler:
DEBUG_SYNC(ha_thd(), "partition_open_error");
while (file-- != m_file)
(*file)->ha_close();
err_alloc:
free_partition_bitmaps();
DBUG_RETURN(error);
}
/*
Disabled since it is not possible to prune yet.
without pruning, it need to rebind/unbind every partition in every
statement which uses a table from the table cache. Will also use
as many PSI_tables as there are partitions.
*/
#ifdef HAVE_M_PSI_PER_PARTITION
void ha_partition::unbind_psi()
{
uint i;
DBUG_ENTER("ha_partition::unbind_psi");
handler::unbind_psi();
for (i= 0; i < m_tot_parts; i++)
{
DBUG_ASSERT(m_file[i] != NULL);
m_file[i]->unbind_psi();
}
DBUG_VOID_RETURN;
}
void ha_partition::rebind_psi()
{
uint i;
DBUG_ENTER("ha_partition::rebind_psi");
handler::rebind_psi();
for (i= 0; i < m_tot_parts; i++)
{
DBUG_ASSERT(m_file[i] != NULL);
m_file[i]->rebind_psi();
}
DBUG_VOID_RETURN;
}
#endif /* HAVE_M_PSI_PER_PARTITION */
/**
Clone the open and locked partitioning handler.
@param mem_root MEM_ROOT to use.
@return Pointer to the successfully created clone or NULL
@details
This function creates a new ha_partition handler as a clone/copy. The
original (this) must already be opened and locked. The clone will use
the originals m_part_info.
It also allocates memory for ref + ref_dup.
In ha_partition::open() it will clone its original handlers partitions
which will allocate then on the correct MEM_ROOT and also open them.
*/
handler *ha_partition::clone(const char *name, MEM_ROOT *mem_root)
{
ha_partition *new_handler;
DBUG_ENTER("ha_partition::clone");
new_handler= new (mem_root) ha_partition(ht, table_share, m_part_info,
this, mem_root);
if (!new_handler)
DBUG_RETURN(NULL);
/*
We will not clone each partition's handler here, it will be done in
ha_partition::open() for clones. Also set_ha_share_ref is not needed
here, since 1) ha_share is copied in the constructor used above
2) each partition's cloned handler will set it from its original.
*/
/*
Allocate new_handler->ref here because otherwise ha_open will allocate it
on this->table->mem_root and we will not be able to reclaim that memory
when the clone handler object is destroyed.
*/
if (!(new_handler->ref= (uchar*) alloc_root(mem_root,
ALIGN_SIZE(m_ref_length)*2)))
goto err;
if (new_handler->ha_open(table, name,
table->db_stat,
HA_OPEN_IGNORE_IF_LOCKED | HA_OPEN_NO_PSI_CALL))
goto err;
DBUG_RETURN((handler*) new_handler);
err:
delete new_handler;
DBUG_RETURN(NULL);
}
/*
Close handler object
SYNOPSIS
close()
RETURN VALUE
>0 Error code
0 Success
DESCRIPTION
Called from sql_base.cc, sql_select.cc, and table.cc.
In sql_select.cc it is only used to close up temporary tables or during
the process where a temporary table is converted over to being a
myisam table.
For sql_base.cc look at close_data_tables().
*/
int ha_partition::close(void)
{
bool first= TRUE;
handler **file;
DBUG_ENTER("ha_partition::close");
DBUG_ASSERT(table->s == table_share);
destroy_record_priority_queue();
free_partition_bitmaps();
DBUG_ASSERT(m_part_info);
file= m_file;
repeat:
do
{
(*file)->ha_close();
} while (*(++file));
if (first && m_added_file && m_added_file[0])
{
file= m_added_file;
first= FALSE;
goto repeat;
}
m_handler_status= handler_closed;
DBUG_RETURN(0);
}
/****************************************************************************
MODULE start/end statement
****************************************************************************/
/*
A number of methods to define various constants for the handler. In
the case of the partition handler we need to use some max and min
of the underlying handlers in most cases.
*/
/*
Set external locks on table
SYNOPSIS
external_lock()
thd Thread object
lock_type Type of external lock
RETURN VALUE
>0 Error code
0 Success
DESCRIPTION
First you should go read the section "locking functions for mysql" in
lock.cc to understand this.
This create a lock on the table. If you are implementing a storage engine
that can handle transactions look at ha_berkeley.cc to see how you will
want to go about doing this. Otherwise you should consider calling
flock() here.
Originally this method was used to set locks on file level to enable
several MySQL Servers to work on the same data. For transactional
engines it has been "abused" to also mean start and end of statements
to enable proper rollback of statements and transactions. When LOCK
TABLES has been issued the start_stmt method takes over the role of
indicating start of statement but in this case there is no end of
statement indicator(?).
Called from lock.cc by lock_external() and unlock_external(). Also called
from sql_table.cc by copy_data_between_tables().
*/
int ha_partition::external_lock(THD *thd, int lock_type)
{
uint error;
uint i, first_used_partition;
MY_BITMAP *used_partitions;
DBUG_ENTER("ha_partition::external_lock");
DBUG_ASSERT(!auto_increment_lock);
DBUG_ASSERT(!auto_increment_safe_stmt_log_lock);
if (lock_type == F_UNLCK)
used_partitions= &m_locked_partitions;
else
used_partitions= &(m_part_info->lock_partitions);
first_used_partition= bitmap_get_first_set(used_partitions);
for (i= first_used_partition;
i < m_tot_parts;
i= bitmap_get_next_set(used_partitions, i))
{
DBUG_PRINT("info", ("external_lock(thd, %d) part %d", lock_type, i));
if ((error= m_file[i]->ha_external_lock(thd, lock_type)))
{
if (lock_type != F_UNLCK)
goto err_handler;
}
DBUG_PRINT("info", ("external_lock part %u lock %d", i, lock_type));
if (lock_type != F_UNLCK)
bitmap_set_bit(&m_locked_partitions, i);
}
if (lock_type == F_UNLCK)
{
bitmap_clear_all(used_partitions);
}
else
{
/* Add touched partitions to be included in reset(). */
bitmap_union(&m_partitions_to_reset, used_partitions);
}
if (m_added_file && m_added_file[0])
{
handler **file= m_added_file;
DBUG_ASSERT(lock_type == F_UNLCK);
do
{
(void) (*file)->ha_external_lock(thd, lock_type);
} while (*(++file));
}
if (lock_type == F_WRLCK && m_part_info->part_expr)
m_part_info->part_expr->walk(&Item::register_field_in_read_map, 1, 0);
DBUG_RETURN(0);
err_handler:
uint j;
for (j= first_used_partition;
j < i;
j= bitmap_get_next_set(&m_locked_partitions, j))
{
(void) m_file[j]->ha_external_lock(thd, F_UNLCK);
}
bitmap_clear_all(&m_locked_partitions);
DBUG_RETURN(error);
}
/*
Get the lock(s) for the table and perform conversion of locks if needed
SYNOPSIS
store_lock()
thd Thread object
to Lock object array
lock_type Table lock type
RETURN VALUE
>0 Error code
0 Success
DESCRIPTION
The idea with handler::store_lock() is the following:
The statement decided which locks we should need for the table
for updates/deletes/inserts we get WRITE locks, for SELECT... we get
read locks.
Before adding the lock into the table lock handler (see thr_lock.c)
mysqld calls store lock with the requested locks. Store lock can now
modify a write lock to a read lock (or some other lock), ignore the
lock (if we don't want to use MySQL table locks at all) or add locks
for many tables (like we do when we are using a MERGE handler).
Berkeley DB for partition changes all WRITE locks to TL_WRITE_ALLOW_WRITE
(which signals that we are doing WRITES, but we are still allowing other
reader's and writer's.
When releasing locks, store_lock() is also called. In this case one
usually doesn't have to do anything.
store_lock is called when holding a global mutex to ensure that only
one thread at a time changes the locking information of tables.
In some exceptional cases MySQL may send a request for a TL_IGNORE;
This means that we are requesting the same lock as last time and this
should also be ignored. (This may happen when someone does a flush
table when we have opened a part of the tables, in which case mysqld
closes and reopens the tables and tries to get the same locks as last
time). In the future we will probably try to remove this.
Called from lock.cc by get_lock_data().
*/
THR_LOCK_DATA **ha_partition::store_lock(THD *thd,
THR_LOCK_DATA **to,
enum thr_lock_type lock_type)
{
uint i;
DBUG_ENTER("ha_partition::store_lock");
DBUG_ASSERT(thd == current_thd);
/*
This can be called from get_lock_data() in mysql_lock_abort_for_thread(),
even when thd != table->in_use. In that case don't use partition pruning,
but use all partitions instead to avoid using another threads structures.
*/
if (thd != table->in_use)
{
for (i= 0; i < m_tot_parts; i++)
to= m_file[i]->store_lock(thd, to, lock_type);
}
else
{
MY_BITMAP *used_partitions= lock_type == TL_UNLOCK ||
lock_type == TL_IGNORE ?
&m_locked_partitions :
&m_part_info->lock_partitions;
for (i= bitmap_get_first_set(used_partitions);
i < m_tot_parts;
i= bitmap_get_next_set(used_partitions, i))
{
DBUG_PRINT("info", ("store lock %d iteration", i));
to= m_file[i]->store_lock(thd, to, lock_type);
}
}
DBUG_RETURN(to);
}
/*
Start a statement when table is locked
SYNOPSIS
start_stmt()
thd Thread object
lock_type Type of external lock
RETURN VALUE
>0 Error code
0 Success
DESCRIPTION
This method is called instead of external lock when the table is locked
before the statement is executed.
*/
int ha_partition::start_stmt(THD *thd, thr_lock_type lock_type)
{
int error= 0;
uint i;
/* Assert that read_partitions is included in lock_partitions */
DBUG_ASSERT(bitmap_is_subset(&m_part_info->read_partitions,
&m_part_info->lock_partitions));
/*
m_locked_partitions is set in previous external_lock/LOCK TABLES.
Current statement's lock requests must not include any partitions
not previously locked.
*/
DBUG_ASSERT(bitmap_is_subset(&m_part_info->lock_partitions,
&m_locked_partitions));
DBUG_ENTER("ha_partition::start_stmt");
for (i= bitmap_get_first_set(&(m_part_info->lock_partitions));
i < m_tot_parts;
i= bitmap_get_next_set(&m_part_info->lock_partitions, i))
{
if ((error= m_file[i]->start_stmt(thd, lock_type)))
break;
/* Add partition to be called in reset(). */
bitmap_set_bit(&m_partitions_to_reset, i);
}
if (lock_type == F_WRLCK && m_part_info->part_expr)
m_part_info->part_expr->walk(&Item::register_field_in_read_map, 1, 0);
DBUG_RETURN(error);
}
/**
Get number of lock objects returned in store_lock
@returns Number of locks returned in call to store_lock
@desc
Returns the number of store locks needed in call to store lock.
We return number of partitions we will lock multiplied with number of
locks needed by each partition. Assists the above functions in allocating
sufficient space for lock structures.
*/
uint ha_partition::lock_count() const
{
DBUG_ENTER("ha_partition::lock_count");
/*
The caller want to know the upper bound, to allocate enough memory.
There is no performance lost if we simply return maximum number locks
needed, only some minor over allocation of memory in get_lock_data().
Also notice that this may be called for another thread != table->in_use,
when mysql_lock_abort_for_thread() is called. So this is more safe, then
using number of partitions after pruning.
*/
DBUG_RETURN(m_tot_parts * m_num_locks);
}
/*
Unlock last accessed row
SYNOPSIS
unlock_row()
RETURN VALUE
NONE
DESCRIPTION
Record currently processed was not in the result set of the statement
and is thus unlocked. Used for UPDATE and DELETE queries.
*/
void ha_partition::unlock_row()
{
DBUG_ENTER("ha_partition::unlock_row");
m_file[m_last_part]->unlock_row();
DBUG_VOID_RETURN;
}
/**
Check if semi consistent read was used
SYNOPSIS
was_semi_consistent_read()
RETURN VALUE
TRUE Previous read was a semi consistent read
FALSE Previous read was not a semi consistent read
DESCRIPTION
See handler.h:
In an UPDATE or DELETE, if the row under the cursor was locked by another
transaction, and the engine used an optimistic read of the last
committed row value under the cursor, then the engine returns 1 from this
function. MySQL must NOT try to update this optimistic value. If the
optimistic value does not match the WHERE condition, MySQL can decide to
skip over this row. Currently only works for InnoDB. This can be used to
avoid unnecessary lock waits.
If this method returns nonzero, it will also signal the storage
engine that the next read will be a locking re-read of the row.
*/
bool ha_partition::was_semi_consistent_read()
{
DBUG_ENTER("ha_partition::was_semi_consistent_read");
DBUG_ASSERT(m_last_part < m_tot_parts);
DBUG_ASSERT(bitmap_is_set(&(m_part_info->read_partitions), m_last_part));
DBUG_RETURN(m_file[m_last_part]->was_semi_consistent_read());
}
/**
Use semi consistent read if possible
SYNOPSIS
try_semi_consistent_read()
yes Turn on semi consistent read
RETURN VALUE
NONE
DESCRIPTION
See handler.h:
Tell the engine whether it should avoid unnecessary lock waits.
If yes, in an UPDATE or DELETE, if the row under the cursor was locked
by another transaction, the engine may try an optimistic read of
the last committed row value under the cursor.
Note: prune_partitions are already called before this call, so using
pruning is OK.
*/
void ha_partition::try_semi_consistent_read(bool yes)
{
uint i;
DBUG_ENTER("ha_partition::try_semi_consistent_read");
i= bitmap_get_first_set(&(m_part_info->read_partitions));
DBUG_ASSERT(i != MY_BIT_NONE);
for (;
i < m_tot_parts;
i= bitmap_get_next_set(&m_part_info->read_partitions, i))
{
m_file[i]->try_semi_consistent_read(yes);
}
DBUG_VOID_RETURN;
}
/****************************************************************************
MODULE change record
****************************************************************************/
/*
Insert a row to the table
SYNOPSIS
write_row()
buf The row in MySQL Row Format
RETURN VALUE
>0 Error code
0 Success
DESCRIPTION
write_row() inserts a row. buf() is a byte array of data, normally
record[0].
You can use the field information to extract the data from the native byte
array type.
Example of this would be:
for (Field **field=table->field ; *field ; field++)
{
...
}
See ha_tina.cc for a variant of extracting all of the data as strings.
ha_berkeley.cc has a variant of how to store it intact by "packing" it
for ha_berkeley's own native storage type.
Called from item_sum.cc, item_sum.cc, sql_acl.cc, sql_insert.cc,
sql_insert.cc, sql_select.cc, sql_table.cc, sql_udf.cc, and sql_update.cc.
ADDITIONAL INFO:
We have to set auto_increment fields, because those may be used in
determining which partition the row should be written to.
*/
int ha_partition::write_row(uchar * buf)
{
uint32 part_id;
int error;
longlong func_value;
bool have_auto_increment= table->next_number_field && buf == table->record[0];
MY_BITMAP *old_map;
THD *thd= ha_thd();
sql_mode_t saved_sql_mode= thd->variables.sql_mode;
bool saved_auto_inc_field_not_null= table->auto_increment_field_not_null;
DBUG_ENTER("ha_partition::write_row");
DBUG_ASSERT(buf == m_rec0);
/*
If we have an auto_increment column and we are writing a changed row
or a new row, then update the auto_increment value in the record.
*/
if (have_auto_increment)
{
if (!part_share->auto_inc_initialized &&
!table_share->next_number_keypart)
{
/*
If auto_increment in table_share is not initialized, start by
initializing it.
*/
info(HA_STATUS_AUTO);
}
error= update_auto_increment();
/*
If we have failed to set the auto-increment value for this row,
it is highly likely that we will not be able to insert it into
the correct partition. We must check and fail if necessary.
*/
if (error)
goto exit;
/*
Don't allow generation of auto_increment value the partitions handler.
If a partitions handler would change the value, then it might not
match the partition any longer.
This can occur if 'SET INSERT_ID = 0; INSERT (NULL)',
So allow this by adding 'MODE_NO_AUTO_VALUE_ON_ZERO' to sql_mode.
The partitions handler::next_insert_id must always be 0. Otherwise
we need to forward release_auto_increment, or reset it for all
partitions.
*/
if (table->next_number_field->val_int() == 0)
{
table->auto_increment_field_not_null= TRUE;
thd->variables.sql_mode|= MODE_NO_AUTO_VALUE_ON_ZERO;
}
}
old_map= dbug_tmp_use_all_columns(table, &table->read_set);
error= m_part_info->get_partition_id(m_part_info, &part_id, &func_value);
dbug_tmp_restore_column_map(&table->read_set, old_map);
if (unlikely(error))
{
m_part_info->err_value= func_value;
goto exit;
}
if (!bitmap_is_set(&(m_part_info->lock_partitions), part_id))
{
DBUG_PRINT("info", ("Write to non-locked partition %u (func_value: %ld)",
part_id, (long) func_value));
error= HA_ERR_NOT_IN_LOCK_PARTITIONS;
goto exit;
}
m_last_part= part_id;
DBUG_PRINT("info", ("Insert in partition %d", part_id));
start_part_bulk_insert(thd, part_id);
tmp_disable_binlog(thd); /* Do not replicate the low-level changes. */
error= m_file[part_id]->ha_write_row(buf);
if (have_auto_increment && !table->s->next_number_keypart)
set_auto_increment_if_higher(table->next_number_field);
reenable_binlog(thd);
exit:
thd->variables.sql_mode= saved_sql_mode;
table->auto_increment_field_not_null= saved_auto_inc_field_not_null;
DBUG_RETURN(error);
}
/*
Update an existing row
SYNOPSIS
update_row()
old_data Old record in MySQL Row Format
new_data New record in MySQL Row Format
RETURN VALUE
>0 Error code
0 Success
DESCRIPTION
Yes, update_row() does what you expect, it updates a row. old_data will
have the previous row record in it, while new_data will have the newest
data in it.
Keep in mind that the server can do updates based on ordering if an
ORDER BY clause was used. Consecutive ordering is not guaranteed.
Called from sql_select.cc, sql_acl.cc, sql_update.cc, and sql_insert.cc.
new_data is always record[0]
old_data is always record[1]
*/
int ha_partition::update_row(const uchar *old_data, uchar *new_data)
{
THD *thd= ha_thd();
uint32 new_part_id, old_part_id;
int error= 0;
longlong func_value;
DBUG_ENTER("ha_partition::update_row");
m_err_rec= NULL;
// Need to read partition-related columns, to locate the row's partition:
DBUG_ASSERT(bitmap_is_subset(&m_part_info->full_part_field_set,
table->read_set));
if ((error= get_parts_for_update(old_data, new_data, table->record[0],
m_part_info, &old_part_id, &new_part_id,
&func_value)))
{
m_part_info->err_value= func_value;
goto exit;
}
DBUG_ASSERT(bitmap_is_set(&(m_part_info->read_partitions), old_part_id));
if (!bitmap_is_set(&(m_part_info->lock_partitions), new_part_id))
{
error= HA_ERR_NOT_IN_LOCK_PARTITIONS;
goto exit;
}
/*
The protocol for updating a row is:
1) position the handler (cursor) on the row to be updated,
either through the last read row (rnd or index) or by rnd_pos.
2) call update_row with both old and new full records as arguments.
This means that m_last_part should already be set to actual partition
where the row was read from. And if that is not the same as the
calculated part_id we found a misplaced row, we return an error to
notify the user that something is broken in the row distribution
between partitions! Since we don't check all rows on read, we return an
error instead of correcting m_last_part, to make the user aware of the
problem!
Notice that HA_READ_BEFORE_WRITE_REMOVAL does not require this protocol,
so this is not supported for this engine.
*/
if (old_part_id != m_last_part)
{
m_err_rec= old_data;
DBUG_RETURN(HA_ERR_ROW_IN_WRONG_PARTITION);
}
m_last_part= new_part_id;
start_part_bulk_insert(thd, new_part_id);
if (new_part_id == old_part_id)
{
DBUG_PRINT("info", ("Update in partition %d", new_part_id));
tmp_disable_binlog(thd); /* Do not replicate the low-level changes. */
error= m_file[new_part_id]->ha_update_row(old_data, new_data);
reenable_binlog(thd);
goto exit;
}
else
{
Field *saved_next_number_field= table->next_number_field;
/*
Don't allow generation of auto_increment value for update.
table->next_number_field is never set on UPDATE.
But is set for INSERT ... ON DUPLICATE KEY UPDATE,
and since update_row() does not generate or update an auto_inc value,
we cannot have next_number_field set when moving a row
to another partition with write_row(), since that could
generate/update the auto_inc value.
This gives the same behavior for partitioned vs non partitioned tables.
*/
table->next_number_field= NULL;
DBUG_PRINT("info", ("Update from partition %d to partition %d",
old_part_id, new_part_id));
tmp_disable_binlog(thd); /* Do not replicate the low-level changes. */
error= m_file[new_part_id]->ha_write_row(new_data);
reenable_binlog(thd);
table->next_number_field= saved_next_number_field;
if (error)
goto exit;
tmp_disable_binlog(thd); /* Do not replicate the low-level changes. */
error= m_file[old_part_id]->ha_delete_row(old_data);
reenable_binlog(thd);
if (error)
{
#ifdef IN_THE_FUTURE
(void) m_file[new_part_id]->delete_last_inserted_row(new_data);
#endif
goto exit;
}
}
exit:
/*
if updating an auto_increment column, update
part_share->next_auto_inc_val if needed.
(not to be used if auto_increment on secondary field in a multi-column
index)
mysql_update does not set table->next_number_field, so we use
table->found_next_number_field instead.
Also checking that the field is marked in the write set.
*/
if (table->found_next_number_field &&
new_data == table->record[0] &&
!table->s->next_number_keypart &&
bitmap_is_set(table->write_set,
table->found_next_number_field->field_index))
{
if (!part_share->auto_inc_initialized)
info(HA_STATUS_AUTO);
set_auto_increment_if_higher(table->found_next_number_field);
}
DBUG_RETURN(error);
}
/*
Remove an existing row
SYNOPSIS
delete_row
buf Deleted row in MySQL Row Format
RETURN VALUE
>0 Error Code
0 Success
DESCRIPTION
This will delete a row. buf will contain a copy of the row to be deleted.
The server will call this right after the current row has been read
(from either a previous rnd_xxx() or index_xxx() call).
If you keep a pointer to the last row or can access a primary key it will
make doing the deletion quite a bit easier.
Keep in mind that the server does no guarantee consecutive deletions.
ORDER BY clauses can be used.
Called in sql_acl.cc and sql_udf.cc to manage internal table information.
Called in sql_delete.cc, sql_insert.cc, and sql_select.cc. In sql_select
it is used for removing duplicates while in insert it is used for REPLACE
calls.
buf is either record[0] or record[1]
*/
int ha_partition::delete_row(const uchar *buf)
{
uint32 part_id;
int error;
THD *thd= ha_thd();
DBUG_ENTER("ha_partition::delete_row");
m_err_rec= NULL;
DBUG_ASSERT(bitmap_is_subset(&m_part_info->full_part_field_set,
table->read_set));
if ((error= get_part_for_delete(buf, m_rec0, m_part_info, &part_id)))
{
DBUG_RETURN(error);
}
/* Should never call delete_row on a partition which is not read */
DBUG_ASSERT(bitmap_is_set(&(m_part_info->read_partitions), part_id));
DBUG_ASSERT(bitmap_is_set(&(m_part_info->lock_partitions), part_id));
if (!bitmap_is_set(&(m_part_info->lock_partitions), part_id))
DBUG_RETURN(HA_ERR_NOT_IN_LOCK_PARTITIONS);
/*
The protocol for deleting a row is:
1) position the handler (cursor) on the row to be deleted,
either through the last read row (rnd or index) or by rnd_pos.
2) call delete_row with the full record as argument.
This means that m_last_part should already be set to actual partition
where the row was read from. And if that is not the same as the
calculated part_id we found a misplaced row, we return an error to
notify the user that something is broken in the row distribution
between partitions! Since we don't check all rows on read, we return an
error instead of forwarding the delete to the correct (m_last_part)
partition!
Notice that HA_READ_BEFORE_WRITE_REMOVAL does not require this protocol,
so this is not supported for this engine.
TODO: change the assert in InnoDB into an error instead and make this one
an assert instead and remove the get_part_for_delete()!
*/
if (part_id != m_last_part)
{
m_err_rec= buf;
DBUG_RETURN(HA_ERR_ROW_IN_WRONG_PARTITION);
}
m_last_part= part_id;
tmp_disable_binlog(thd);
error= m_file[part_id]->ha_delete_row(buf);
reenable_binlog(thd);
DBUG_RETURN(error);
}
/*
Delete all rows in a table
SYNOPSIS
delete_all_rows()
RETURN VALUE
>0 Error Code
0 Success
DESCRIPTION
Used to delete all rows in a table. Both for cases of truncate and
for cases where the optimizer realizes that all rows will be
removed as a result of a SQL statement.
Called from item_sum.cc by Item_func_group_concat::clear(),
Item_sum_count::clear(), and Item_func_group_concat::clear().
Called from sql_delete.cc by mysql_delete().
Called from sql_select.cc by JOIN::reset().
Called from sql_union.cc by st_select_lex_unit::exec().
*/
int ha_partition::delete_all_rows()
{
int error;
uint i;
DBUG_ENTER("ha_partition::delete_all_rows");
for (i= bitmap_get_first_set(&m_part_info->read_partitions);
i < m_tot_parts;
i= bitmap_get_next_set(&m_part_info->read_partitions, i))
{
/* Can be pruned, like DELETE FROM t PARTITION (pX) */
if ((error= m_file[i]->ha_delete_all_rows()))
DBUG_RETURN(error);
}
DBUG_RETURN(0);
}
/**
Manually truncate the table.
@retval 0 Success.
@retval > 0 Error code.
*/
int ha_partition::truncate()
{
int error;
handler **file;
DBUG_ENTER("ha_partition::truncate");
/*
TRUNCATE also means resetting auto_increment. Hence, reset
it so that it will be initialized again at the next use.
*/
lock_auto_increment();
part_share->next_auto_inc_val= 0;
part_share->auto_inc_initialized= false;
unlock_auto_increment();
file= m_file;
do
{
if ((error= (*file)->ha_truncate()))
DBUG_RETURN(error);
} while (*(++file));
DBUG_RETURN(0);
}
/**
Truncate a set of specific partitions.
@remark Auto increment value will be truncated in that partition as well!
ALTER TABLE t TRUNCATE PARTITION ...
*/
int ha_partition::truncate_partition(Alter_info *alter_info, bool *binlog_stmt)
{
int error= 0;
List_iterator<partition_element> part_it(m_part_info->partitions);
uint num_parts= m_part_info->num_parts;
uint num_subparts= m_part_info->num_subparts;
uint i= 0;
DBUG_ENTER("ha_partition::truncate_partition");
/* Only binlog when it starts any call to the partitions handlers */
*binlog_stmt= false;
if (set_part_state(alter_info, m_part_info, PART_ADMIN))
DBUG_RETURN(HA_ERR_NO_PARTITION_FOUND);
/*
TRUNCATE also means resetting auto_increment. Hence, reset
it so that it will be initialized again at the next use.
*/
lock_auto_increment();
part_share->next_auto_inc_val= 0;
part_share->auto_inc_initialized= FALSE;
unlock_auto_increment();
*binlog_stmt= true;
do
{
partition_element *part_elem= part_it++;
if (part_elem->part_state == PART_ADMIN)
{
if (m_is_sub_partitioned)
{
List_iterator<partition_element>
subpart_it(part_elem->subpartitions);
partition_element *sub_elem;
uint j= 0, part;
do
{
sub_elem= subpart_it++;
part= i * num_subparts + j;
DBUG_PRINT("info", ("truncate subpartition %u (%s)",
part, sub_elem->partition_name));
if ((error= m_file[part]->ha_truncate()))
break;
sub_elem->part_state= PART_NORMAL;
} while (++j < num_subparts);
}
else
{
DBUG_PRINT("info", ("truncate partition %u (%s)", i,
part_elem->partition_name));
error= m_file[i]->ha_truncate();
}
part_elem->part_state= PART_NORMAL;
}
} while (!error && (++i < num_parts));
DBUG_RETURN(error);
}
/*
Start a large batch of insert rows
SYNOPSIS
start_bulk_insert()
rows Number of rows to insert
flags Flags to control index creation
RETURN VALUE
NONE
DESCRIPTION
rows == 0 means we will probably insert many rows
*/
void ha_partition::start_bulk_insert(ha_rows rows, uint flags)
{
DBUG_ENTER("ha_partition::start_bulk_insert");
m_bulk_inserted_rows= 0;
bitmap_clear_all(&m_bulk_insert_started);
/* use the last bit for marking if bulk_insert_started was called */
bitmap_set_bit(&m_bulk_insert_started, m_tot_parts);
DBUG_VOID_RETURN;
}
/*
Check if start_bulk_insert has been called for this partition,
if not, call it and mark it called
*/
void ha_partition::start_part_bulk_insert(THD *thd, uint part_id)
{
long old_buffer_size;
if (!bitmap_is_set(&m_bulk_insert_started, part_id) &&
bitmap_is_set(&m_bulk_insert_started, m_tot_parts))
{
DBUG_ASSERT(bitmap_is_set(&(m_part_info->lock_partitions), part_id));
old_buffer_size= thd->variables.read_buff_size;
/* Update read_buffer_size for this partition */
thd->variables.read_buff_size= estimate_read_buffer_size(old_buffer_size);
m_file[part_id]->ha_start_bulk_insert(guess_bulk_insert_rows());
bitmap_set_bit(&m_bulk_insert_started, part_id);
thd->variables.read_buff_size= old_buffer_size;
}
m_bulk_inserted_rows++;
}
/*
Estimate the read buffer size for each partition.
SYNOPSIS
ha_partition::estimate_read_buffer_size()
original_size read buffer size originally set for the server
RETURN VALUE
estimated buffer size.
DESCRIPTION
If the estimated number of rows to insert is less than 10 (but not 0)
the new buffer size is same as original buffer size.
In case of first partition of when partition function is monotonic
new buffer size is same as the original buffer size.
For rest of the partition total buffer of 10*original_size is divided
equally if number of partition is more than 10 other wise each partition
will be allowed to use original buffer size.
*/
long ha_partition::estimate_read_buffer_size(long original_size)
{
/*
If number of rows to insert is less than 10, but not 0,
return original buffer size.
*/
if (estimation_rows_to_insert && (estimation_rows_to_insert < 10))
return (original_size);
/*
If first insert/partition and monotonic partition function,
allow using buffer size originally set.
*/
if (!m_bulk_inserted_rows &&
m_part_func_monotonicity_info != NON_MONOTONIC &&
m_tot_parts > 1)
return original_size;
/*
Allow total buffer used in all partition to go up to 10*read_buffer_size.
11*read_buffer_size in case of monotonic partition function.
*/
if (m_tot_parts < 10)
return original_size;
return (original_size * 10 / m_tot_parts);
}
/*
Try to predict the number of inserts into this partition.
If less than 10 rows (including 0 which means Unknown)
just give that as a guess
If monotonic partitioning function was used
guess that 50 % of the inserts goes to the first partition
For all other cases, guess on equal distribution between the partitions
*/
ha_rows ha_partition::guess_bulk_insert_rows()
{
DBUG_ENTER("guess_bulk_insert_rows");
if (estimation_rows_to_insert < 10)
DBUG_RETURN(estimation_rows_to_insert);
/* If first insert/partition and monotonic partition function, guess 50%. */
if (!m_bulk_inserted_rows &&
m_part_func_monotonicity_info != NON_MONOTONIC &&
m_tot_parts > 1)
DBUG_RETURN(estimation_rows_to_insert / 2);
/* Else guess on equal distribution (+1 is to avoid returning 0/Unknown) */
if (m_bulk_inserted_rows < estimation_rows_to_insert)
DBUG_RETURN(((estimation_rows_to_insert - m_bulk_inserted_rows)
/ m_tot_parts) + 1);
/* The estimation was wrong, must say 'Unknown' */
DBUG_RETURN(0);
}
/*
Finish a large batch of insert rows
SYNOPSIS
end_bulk_insert()
RETURN VALUE
>0 Error code
0 Success
Note: end_bulk_insert can be called without start_bulk_insert
being called, see bug#44108.
*/
int ha_partition::end_bulk_insert()
{
int error= 0;
uint i;
DBUG_ENTER("ha_partition::end_bulk_insert");
if (!bitmap_is_set(&m_bulk_insert_started, m_tot_parts))
DBUG_RETURN(error);
for (i= bitmap_get_first_set(&m_bulk_insert_started);
i < m_tot_parts;
i= bitmap_get_next_set(&m_bulk_insert_started, i))
{
int tmp;
if ((tmp= m_file[i]->ha_end_bulk_insert()))
error= tmp;
}
bitmap_clear_all(&m_bulk_insert_started);
DBUG_RETURN(error);
}
/****************************************************************************
MODULE full table scan
****************************************************************************/
/*
Initialize engine for random reads
SYNOPSIS
ha_partition::rnd_init()
scan 0 Initialize for random reads through rnd_pos()
1 Initialize for random scan through rnd_next()
RETURN VALUE
>0 Error code
0 Success
DESCRIPTION
rnd_init() is called when the server wants the storage engine to do a
table scan or when the server wants to access data through rnd_pos.
When scan is used we will scan one handler partition at a time.
When preparing for rnd_pos we will init all handler partitions.
No extra cache handling is needed when scanning is not performed.
Before initialising we will call rnd_end to ensure that we clean up from
any previous incarnation of a table scan.
Called from filesort.cc, records.cc, sql_handler.cc, sql_select.cc,
sql_table.cc, and sql_update.cc.
*/
int ha_partition::rnd_init(bool scan)
{
int error;
uint i= 0;
uint32 part_id;
DBUG_ENTER("ha_partition::rnd_init");
/*
For operations that may need to change data, we may need to extend
read_set.
*/
if (get_lock_type() == F_WRLCK)
{
/*
If write_set contains any of the fields used in partition and
subpartition expression, we need to set all bits in read_set because
the row may need to be inserted in a different [sub]partition. In
other words update_row() can be converted into write_row(), which
requires a complete record.
*/
if (bitmap_is_overlapping(&m_part_info->full_part_field_set,
table->write_set))
bitmap_set_all(table->read_set);
else
{
/*
Some handlers only read fields as specified by the bitmap for the
read set. For partitioned handlers we always require that the
fields of the partition functions are read such that we can
calculate the partition id to place updated and deleted records.
*/
bitmap_union(table->read_set, &m_part_info->full_part_field_set);
}
}
/* Now we see what the index of our first important partition is */
DBUG_PRINT("info", ("m_part_info->read_partitions: %p",
m_part_info->read_partitions.bitmap));
part_id= bitmap_get_first_set(&(m_part_info->read_partitions));
DBUG_PRINT("info", ("m_part_spec.start_part %d", part_id));
if (MY_BIT_NONE == part_id)
{
error= 0;
goto err1;
}
/*
We have a partition and we are scanning with rnd_next
so we bump our cache
*/
DBUG_PRINT("info", ("rnd_init on partition %d", part_id));
if (scan)
{
/*
rnd_end() is needed for partitioning to reset internal data if scan
is already in use
*/
rnd_end();
late_extra_cache(part_id);
if ((error= m_file[part_id]->ha_rnd_init(scan)))
goto err;
}
else
{
for (i= part_id;
i < m_tot_parts;
i= bitmap_get_next_set(&m_part_info->read_partitions, i))
{
if ((error= m_file[i]->ha_rnd_init(scan)))
goto err;
}
}
m_scan_value= scan;
m_part_spec.start_part= part_id;
m_part_spec.end_part= m_tot_parts - 1;
DBUG_PRINT("info", ("m_scan_value=%d", m_scan_value));
DBUG_RETURN(0);
err:
/* Call rnd_end for all previously inited partitions. */
for (;
part_id < i;
part_id= bitmap_get_next_set(&m_part_info->read_partitions, part_id))
{
m_file[part_id]->ha_rnd_end();
}
err1:
m_scan_value= 2;
m_part_spec.start_part= NO_CURRENT_PART_ID;
DBUG_RETURN(error);
}
/*
End of a table scan
SYNOPSIS
rnd_end()
RETURN VALUE
>0 Error code
0 Success
*/
int ha_partition::rnd_end()
{
DBUG_ENTER("ha_partition::rnd_end");
switch (m_scan_value) {
case 2: // Error
break;
case 1:
if (NO_CURRENT_PART_ID != m_part_spec.start_part) // Table scan
{
late_extra_no_cache(m_part_spec.start_part);
m_file[m_part_spec.start_part]->ha_rnd_end();
}
break;
case 0:
uint i;
for (i= bitmap_get_first_set(&m_part_info->read_partitions);
i < m_tot_parts;
i= bitmap_get_next_set(&m_part_info->read_partitions, i))
{
m_file[i]->ha_rnd_end();
}
break;
}
m_scan_value= 2;
m_part_spec.start_part= NO_CURRENT_PART_ID;
DBUG_RETURN(0);
}
/*
read next row during full table scan (scan in random row order)
SYNOPSIS
rnd_next()
buf buffer that should be filled with data
RETURN VALUE
>0 Error code
0 Success
DESCRIPTION
This is called for each row of the table scan. When you run out of records
you should return HA_ERR_END_OF_FILE.
The Field structure for the table is the key to getting data into buf
in a manner that will allow the server to understand it.
Called from filesort.cc, records.cc, sql_handler.cc, sql_select.cc,
sql_table.cc, and sql_update.cc.
*/
int ha_partition::rnd_next(uchar *buf)
{
handler *file;
int result= HA_ERR_END_OF_FILE;
uint part_id= m_part_spec.start_part;
DBUG_ENTER("ha_partition::rnd_next");
/* upper level will increment this once again at end of call */
decrement_statistics(&SSV::ha_read_rnd_next_count);
if (NO_CURRENT_PART_ID == part_id)
{
/*
The original set of partitions to scan was empty and thus we report
the result here.
*/
goto end;
}
DBUG_ASSERT(m_scan_value == 1);
file= m_file[part_id];
while (TRUE)
{
result= file->ha_rnd_next(buf);
if (!result)
{
m_last_part= part_id;
m_part_spec.start_part= part_id;
table->status= 0;
DBUG_RETURN(0);
}
/*
if we get here, then the current partition ha_rnd_next returned failure
*/
if (result == HA_ERR_RECORD_DELETED)
continue; // Probably MyISAM
if (result != HA_ERR_END_OF_FILE)
goto end_dont_reset_start_part; // Return error
/* End current partition */
late_extra_no_cache(part_id);
DBUG_PRINT("info", ("rnd_end on partition %d", part_id));
if ((result= file->ha_rnd_end()))
break;
/* Shift to next partition */
part_id= bitmap_get_next_set(&m_part_info->read_partitions, part_id);
if (part_id >= m_tot_parts)
{
result= HA_ERR_END_OF_FILE;
break;
}
m_last_part= part_id;
m_part_spec.start_part= part_id;
file= m_file[part_id];
DBUG_PRINT("info", ("rnd_init on partition %d", part_id));
if ((result= file->ha_rnd_init(1)))
break;
late_extra_cache(part_id);
}
end:
m_part_spec.start_part= NO_CURRENT_PART_ID;
end_dont_reset_start_part:
DBUG_RETURN(result);
}
/*
Save position of current row
SYNOPSIS
position()
record Current record in MySQL Row Format
RETURN VALUE
NONE
DESCRIPTION
position() is called after each call to rnd_next() if the data needs
to be ordered. You can do something like the following to store
the position:
ha_store_ptr(ref, ref_length, current_position);
The server uses ref to store data. ref_length in the above case is
the size needed to store current_position. ref is just a byte array
that the server will maintain. If you are using offsets to mark rows, then
current_position should be the offset. If it is a primary key like in
BDB, then it needs to be a primary key.
Called from filesort.cc, sql_select.cc, sql_delete.cc and sql_update.cc.
*/
void ha_partition::position(const uchar *record)
{
handler *file= m_file[m_last_part];
uint pad_length;
DBUG_ASSERT(bitmap_is_set(&(m_part_info->read_partitions), m_last_part));
DBUG_ENTER("ha_partition::position");
file->position(record);
int2store(ref, m_last_part);
memcpy((ref + PARTITION_BYTES_IN_POS), file->ref, file->ref_length);
pad_length= m_ref_length - PARTITION_BYTES_IN_POS - file->ref_length;
if (pad_length)
memset((ref + PARTITION_BYTES_IN_POS + file->ref_length), 0, pad_length);
DBUG_VOID_RETURN;
}
/*
Read row using position
SYNOPSIS
rnd_pos()
out:buf Row read in MySQL Row Format
position Position of read row
RETURN VALUE
>0 Error code
0 Success
DESCRIPTION
This is like rnd_next, but you are given a position to use
to determine the row. The position will be of the type that you stored in
ref. You can use ha_get_ptr(pos,ref_length) to retrieve whatever key
or position you saved when position() was called.
Called from filesort.cc records.cc sql_insert.cc sql_select.cc
sql_update.cc.
*/
int ha_partition::rnd_pos(uchar * buf, uchar *pos)
{
uint part_id;
handler *file;
DBUG_ENTER("ha_partition::rnd_pos");
decrement_statistics(&SSV::ha_read_rnd_count);
part_id= uint2korr((const uchar *) pos);
DBUG_ASSERT(part_id < m_tot_parts);
file= m_file[part_id];
DBUG_ASSERT(bitmap_is_set(&(m_part_info->read_partitions), part_id));
m_last_part= part_id;
DBUG_RETURN(file->ha_rnd_pos(buf, (pos + PARTITION_BYTES_IN_POS)));
}
/*
Read row using position using given record to find
SYNOPSIS
rnd_pos_by_record()
record Current record in MySQL Row Format
RETURN VALUE
>0 Error code
0 Success
DESCRIPTION
this works as position()+rnd_pos() functions, but does some extra work,
calculating m_last_part - the partition to where the 'record'
should go.
called from replication (log_event.cc)
*/
int ha_partition::rnd_pos_by_record(uchar *record)
{
DBUG_ENTER("ha_partition::rnd_pos_by_record");
if (unlikely(get_part_for_delete(record, m_rec0, m_part_info, &m_last_part)))
DBUG_RETURN(1);
int err= m_file[m_last_part]->rnd_pos_by_record(record);
DBUG_RETURN(err);
}
/****************************************************************************
MODULE index scan
****************************************************************************/
/*
Positions an index cursor to the index specified in the handle. Fetches the
row if available. If the key value is null, begin at the first key of the
index.
There are loads of optimisations possible here for the partition handler.
The same optimisations can also be checked for full table scan although
only through conditions and not from index ranges.
Phase one optimisations:
Check if the fields of the partition function are bound. If so only use
the single partition it becomes bound to.
Phase two optimisations:
If it can be deducted through range or list partitioning that only a
subset of the partitions are used, then only use those partitions.
*/
/**
Setup the ordered record buffer and the priority queue.
*/
bool ha_partition::init_record_priority_queue()
{
DBUG_ENTER("ha_partition::init_record_priority_queue");
DBUG_ASSERT(!m_ordered_rec_buffer);
/*
Initialize the ordered record buffer.
*/
if (!m_ordered_rec_buffer)
{
uint alloc_len;
uint used_parts= bitmap_bits_set(&m_part_info->read_partitions);
/* Allocate record buffer for each used partition. */
m_priority_queue_rec_len= m_rec_length + PARTITION_BYTES_IN_POS;
if (!m_using_extended_keys)
m_priority_queue_rec_len += m_file[0]->ref_length;
alloc_len= used_parts * m_priority_queue_rec_len;
/* Allocate a key for temporary use when setting up the scan. */
alloc_len+= table_share->max_key_length;
if (!(m_ordered_rec_buffer= (uchar*)my_malloc(alloc_len, MYF(MY_WME))))
DBUG_RETURN(true);
/*
We set-up one record per partition and each record has 2 bytes in
front where the partition id is written. This is used by ordered
index_read.
We also set-up a reference to the first record for temporary use in
setting up the scan.
*/
char *ptr= (char*) m_ordered_rec_buffer;
uint i;
for (i= bitmap_get_first_set(&m_part_info->read_partitions);
i < m_tot_parts;
i= bitmap_get_next_set(&m_part_info->read_partitions, i))
{
DBUG_PRINT("info", ("init rec-buf for part %u", i));
int2store(ptr, i);
ptr+= m_priority_queue_rec_len;
}
m_start_key.key= (const uchar*)ptr;
/* Initialize priority queue, initialized to reading forward. */
int (*cmp_func)(void *, uchar *, uchar *);
void *cmp_arg;
if (!m_using_extended_keys)
{
cmp_func= cmp_key_rowid_part_id;
cmp_arg= (void*)this;
}
else
{
cmp_func= cmp_key_part_id;
cmp_arg= (void*)m_curr_key_info;
}
if (init_queue(&m_queue, used_parts, 0, 0, cmp_func, cmp_arg, 0, 0))
{
my_free(m_ordered_rec_buffer);
m_ordered_rec_buffer= NULL;
DBUG_RETURN(true);
}
}
DBUG_RETURN(false);
}
/**
Destroy the ordered record buffer and the priority queue.
*/
void ha_partition::destroy_record_priority_queue()
{
DBUG_ENTER("ha_partition::destroy_record_priority_queue");
if (m_ordered_rec_buffer)
{
delete_queue(&m_queue);
my_free(m_ordered_rec_buffer);
m_ordered_rec_buffer= NULL;
}
DBUG_VOID_RETURN;
}
/*
Initialize handler before start of index scan
SYNOPSIS
index_init()
inx Index number
sorted Is rows to be returned in sorted order
RETURN VALUE
>0 Error code
0 Success
DESCRIPTION
index_init is always called before starting index scans (except when
starting through index_read_idx and using read_range variants).
*/
int ha_partition::index_init(uint inx, bool sorted)
{
int error= 0;
uint i;
DBUG_ENTER("ha_partition::index_init");
DBUG_PRINT("info", ("inx %u sorted %u", inx, sorted));
active_index= inx;
m_part_spec.start_part= NO_CURRENT_PART_ID;
m_start_key.length= 0;
m_ordered= sorted;
m_ordered_scan_ongoing= FALSE;
m_curr_key_info[0]= table->key_info+inx;
if (m_pkey_is_clustered && table->s->primary_key != MAX_KEY)
{
/*
if PK is clustered, then the key cmp must use the pk to
differentiate between equal key in given index.
*/
DBUG_PRINT("info", ("Clustered pk, using pk as secondary cmp"));
m_curr_key_info[1]= table->key_info+table->s->primary_key;
m_curr_key_info[2]= NULL;
m_using_extended_keys= TRUE;
}
else
{
m_curr_key_info[1]= NULL;
m_using_extended_keys= FALSE;
}
if (init_record_priority_queue())
DBUG_RETURN(HA_ERR_OUT_OF_MEM);
/*
Some handlers only read fields as specified by the bitmap for the
read set. For partitioned handlers we always require that the
fields of the partition functions are read such that we can
calculate the partition id to place updated and deleted records.
But this is required for operations that may need to change data only.
*/
if (get_lock_type() == F_WRLCK)
bitmap_union(table->read_set, &m_part_info->full_part_field_set);
if (sorted)
{
/*
An ordered scan is requested. We must make sure all fields of the
used index are in the read set, as partitioning requires them for
sorting (see ha_partition::handle_ordered_index_scan).
The SQL layer may request an ordered index scan without having index
fields in the read set when
- it needs to do an ordered scan over an index prefix.
- it evaluates ORDER BY with SELECT COUNT(*) FROM t1.
TODO: handle COUNT(*) queries via unordered scan.
*/
KEY **key_info= m_curr_key_info;
do
{
for (i= 0; i < (*key_info)->user_defined_key_parts; i++)
bitmap_set_bit(table->read_set,
(*key_info)->key_part[i].field->field_index);
} while (*(++key_info));
}
for (i= bitmap_get_first_set(&m_part_info->read_partitions);
i < m_tot_parts;
i= bitmap_get_next_set(&m_part_info->read_partitions, i))
{
if ((error= m_file[i]->ha_index_init(inx, sorted)))
goto err;
DBUG_EXECUTE_IF("ha_partition_fail_index_init", {
i++;
error= HA_ERR_NO_PARTITION_FOUND;
goto err;
});
}
err:
if (error)
{
/* End the previously initialized indexes. */
uint j;
for (j= bitmap_get_first_set(&m_part_info->read_partitions);
j < i;
j= bitmap_get_next_set(&m_part_info->read_partitions, j))
{
(void) m_file[j]->ha_index_end();
}
destroy_record_priority_queue();
}
DBUG_RETURN(error);
}
/*
End of index scan
SYNOPSIS
index_end()
RETURN VALUE
>0 Error code
0 Success
DESCRIPTION
index_end is called at the end of an index scan to clean up any
things needed to clean up.
*/
int ha_partition::index_end()
{
int error= 0;
uint i;
DBUG_ENTER("ha_partition::index_end");
active_index= MAX_KEY;
m_part_spec.start_part= NO_CURRENT_PART_ID;
for (i= bitmap_get_first_set(&m_part_info->read_partitions);
i < m_tot_parts;
i= bitmap_get_next_set(&m_part_info->read_partitions, i))
{
int tmp;
if ((tmp= m_file[i]->ha_index_end()))
error= tmp;
}
destroy_record_priority_queue();
DBUG_RETURN(error);
}
/*
Read one record in an index scan and start an index scan
SYNOPSIS
index_read_map()
buf Read row in MySQL Row Format
key Key parts in consecutive order
keypart_map Which part of key is used
find_flag What type of key condition is used
RETURN VALUE
>0 Error code
0 Success
DESCRIPTION
index_read_map starts a new index scan using a start key. The MySQL Server
will check the end key on its own. Thus to function properly the
partitioned handler need to ensure that it delivers records in the sort
order of the MySQL Server.
index_read_map can be restarted without calling index_end on the previous
index scan and without calling index_init. In this case the index_read_map
is on the same index as the previous index_scan. This is particularly
used in conjuntion with multi read ranges.
*/
int ha_partition::index_read_map(uchar *buf, const uchar *key,
key_part_map keypart_map,
enum ha_rkey_function find_flag)
{
DBUG_ENTER("ha_partition::index_read_map");
decrement_statistics(&SSV::ha_read_key_count);
end_range= 0;
m_index_scan_type= partition_index_read;
m_start_key.key= key;
m_start_key.keypart_map= keypart_map;
m_start_key.flag= find_flag;
DBUG_RETURN(common_index_read(buf, TRUE));
}
/* Compare two part_no partition numbers */
static int cmp_part_ids(uchar *ref1, uchar *ref2)
{
/* The following was taken from ha_partition::cmp_ref */
my_ptrdiff_t diff1= ref2[1] - ref1[1];
my_ptrdiff_t diff2= ref2[0] - ref1[0];
if (!diff1 && !diff2)
return 0;
if (diff1 > 0)
return(-1);
if (diff1 < 0)
return(+1);
if (diff2 > 0)
return(-1);
return(+1);
}
/*
@brief
Provide ordering by (key_value, part_no).
*/
extern "C" int cmp_key_part_id(void *key_p, uchar *ref1, uchar *ref2)
{
int res;
if ((res= key_rec_cmp(key_p, ref1 + PARTITION_BYTES_IN_POS,
ref2 + PARTITION_BYTES_IN_POS)))
{
return res;
}
return cmp_part_ids(ref1, ref2);
}
/*
@brief
Provide ordering by (key_value, underying_table_rowid, part_no).
*/
extern "C" int cmp_key_rowid_part_id(void *ptr, uchar *ref1, uchar *ref2)
{
ha_partition *file= (ha_partition*)ptr;
int res;
if ((res= key_rec_cmp(file->m_curr_key_info, ref1 + PARTITION_BYTES_IN_POS,
ref2 + PARTITION_BYTES_IN_POS)))
{
return res;
}
if ((res= file->m_file[0]->cmp_ref(ref1 + PARTITION_BYTES_IN_POS + file->m_rec_length,
ref2 + PARTITION_BYTES_IN_POS + file->m_rec_length)))
{
return res;
}
return cmp_part_ids(ref1, ref2);
}
/**
Common routine for a number of index_read variants
@param buf Buffer where the record should be returned.
@param have_start_key TRUE <=> the left endpoint is available, i.e.
we're in index_read call or in read_range_first
call and the range has left endpoint.
FALSE <=> there is no left endpoint (we're in
read_range_first() call and the range has no left
endpoint).
@return Operation status
@retval 0 OK
@retval HA_ERR_END_OF_FILE Whole index scanned, without finding the record.
@retval HA_ERR_KEY_NOT_FOUND Record not found, but index cursor positioned.
@retval other error code.
@details
Start scanning the range (when invoked from read_range_first()) or doing
an index lookup (when invoked from index_read_XXX):
- If possible, perform partition selection
- Find the set of partitions we're going to use
- Depending on whether we need ordering:
NO: Get the first record from first used partition (see
handle_unordered_scan_next_partition)
YES: Fill the priority queue and get the record that is the first in
the ordering
*/
int ha_partition::common_index_read(uchar *buf, bool have_start_key)
{
int error;
uint UNINIT_VAR(key_len); /* used if have_start_key==TRUE */
bool reverse_order= FALSE;
DBUG_ENTER("ha_partition::common_index_read");
DBUG_PRINT("info", ("m_ordered %u m_ordered_scan_ong %u",
m_ordered, m_ordered_scan_ongoing));
if (have_start_key)
{
m_start_key.length= key_len= calculate_key_len(table, active_index,
m_start_key.key,
m_start_key.keypart_map);
DBUG_PRINT("info", ("have_start_key map %lu find_flag %u len %u",
m_start_key.keypart_map, m_start_key.flag, key_len));
DBUG_ASSERT(key_len);
}
if ((error= partition_scan_set_up(buf, have_start_key)))
{
DBUG_RETURN(error);
}
if (have_start_key &&
(m_start_key.flag == HA_READ_PREFIX_LAST ||
m_start_key.flag == HA_READ_PREFIX_LAST_OR_PREV ||
m_start_key.flag == HA_READ_BEFORE_KEY))
{
reverse_order= TRUE;
m_ordered_scan_ongoing= TRUE;
}
DBUG_PRINT("info", ("m_ordered %u m_o_scan_ong %u have_start_key %u",
m_ordered, m_ordered_scan_ongoing, have_start_key));
if (!m_ordered_scan_ongoing)
{
/*
We use unordered index scan when read_range is used and flag
is set to not use ordered.
We also use an unordered index scan when the number of partitions to
scan is only one.
The unordered index scan will use the partition set created.
*/
DBUG_PRINT("info", ("doing unordered scan"));
error= handle_unordered_scan_next_partition(buf);
}
else
{
/*
In all other cases we will use the ordered index scan. This will use
the partition set created by the get_partition_set method.
*/
error= handle_ordered_index_scan(buf, reverse_order);
}
DBUG_RETURN(error);
}
/*
Start an index scan from leftmost record and return first record
SYNOPSIS
index_first()
buf Read row in MySQL Row Format
RETURN VALUE
>0 Error code
0 Success
DESCRIPTION
index_first() asks for the first key in the index.
This is similar to index_read except that there is no start key since
the scan starts from the leftmost entry and proceeds forward with
index_next.
Called from opt_range.cc, opt_sum.cc, sql_handler.cc,
and sql_select.cc.
*/
int ha_partition::index_first(uchar * buf)
{
DBUG_ENTER("ha_partition::index_first");
decrement_statistics(&SSV::ha_read_first_count);
end_range= 0;
m_index_scan_type= partition_index_first;
DBUG_RETURN(common_first_last(buf));
}
/*
Start an index scan from rightmost record and return first record
SYNOPSIS
index_last()
buf Read row in MySQL Row Format
RETURN VALUE
>0 Error code
0 Success
DESCRIPTION
index_last() asks for the last key in the index.
This is similar to index_read except that there is no start key since
the scan starts from the rightmost entry and proceeds forward with
index_prev.
Called from opt_range.cc, opt_sum.cc, sql_handler.cc,
and sql_select.cc.
*/
int ha_partition::index_last(uchar * buf)
{
DBUG_ENTER("ha_partition::index_last");
decrement_statistics(&SSV::ha_read_last_count);
m_index_scan_type= partition_index_last;
DBUG_RETURN(common_first_last(buf));
}
/*
Common routine for index_first/index_last
SYNOPSIS
ha_partition::common_first_last()
see index_first for rest
*/
int ha_partition::common_first_last(uchar *buf)
{
int error;
if ((error= partition_scan_set_up(buf, FALSE)))
return error;
if (!m_ordered_scan_ongoing &&
m_index_scan_type != partition_index_last)
return handle_unordered_scan_next_partition(buf);
return handle_ordered_index_scan(buf, FALSE);
}
/*
Optimization of the default implementation to take advantage of dynamic
partition pruning.
*/
int ha_partition::index_read_idx_map(uchar *buf, uint index,
const uchar *key,
key_part_map keypart_map,
enum ha_rkey_function find_flag)
{
int error= HA_ERR_KEY_NOT_FOUND;
DBUG_ENTER("ha_partition::index_read_idx_map");
if (find_flag == HA_READ_KEY_EXACT)
{
uint part;
m_start_key.key= key;
m_start_key.keypart_map= keypart_map;
m_start_key.flag= find_flag;
m_start_key.length= calculate_key_len(table, index, m_start_key.key,
m_start_key.keypart_map);
get_partition_set(table, buf, index, &m_start_key, &m_part_spec);
/*
We have either found exactly 1 partition
(in which case start_part == end_part)
or no matching partitions (start_part > end_part)
*/
DBUG_ASSERT(m_part_spec.start_part >= m_part_spec.end_part);
/* The start part is must be marked as used. */
DBUG_ASSERT(m_part_spec.start_part > m_part_spec.end_part ||
bitmap_is_set(&(m_part_info->read_partitions),
m_part_spec.start_part));
for (part= m_part_spec.start_part;
part <= m_part_spec.end_part;
part= bitmap_get_next_set(&m_part_info->read_partitions, part))
{
error= m_file[part]->ha_index_read_idx_map(buf, index, key,
keypart_map, find_flag);
if (error != HA_ERR_KEY_NOT_FOUND &&
error != HA_ERR_END_OF_FILE)
break;
}
if (part <= m_part_spec.end_part)
m_last_part= part;
}
else
{
/*
If not only used with READ_EXACT, we should investigate if possible
to optimize for other find_flag's as well.
*/
DBUG_ASSERT(0);
/* fall back on the default implementation */
error= handler::index_read_idx_map(buf, index, key, keypart_map, find_flag);
}
DBUG_RETURN(error);
}
/*
Read next record in a forward index scan
SYNOPSIS
index_next()
buf Read row in MySQL Row Format
RETURN VALUE
>0 Error code
0 Success
DESCRIPTION
Used to read forward through the index.
*/
int ha_partition::index_next(uchar * buf)
{
DBUG_ENTER("ha_partition::index_next");
decrement_statistics(&SSV::ha_read_next_count);
/*
TODO(low priority):
If we want partition to work with the HANDLER commands, we
must be able to do index_last() -> index_prev() -> index_next()
and if direction changes, we must step back those partitions in
the record queue so we don't return a value from the wrong direction.
*/
DBUG_ASSERT(m_index_scan_type != partition_index_last);
if (!m_ordered_scan_ongoing)
{
DBUG_RETURN(handle_unordered_next(buf, FALSE));
}
DBUG_RETURN(handle_ordered_next(buf, FALSE));
}
/*
Read next record special
SYNOPSIS
index_next_same()
buf Read row in MySQL Row Format
key Key
keylen Length of key
RETURN VALUE
>0 Error code
0 Success
DESCRIPTION
This routine is used to read the next but only if the key is the same
as supplied in the call.
*/
int ha_partition::index_next_same(uchar *buf, const uchar *key, uint keylen)
{
DBUG_ENTER("ha_partition::index_next_same");
decrement_statistics(&SSV::ha_read_next_count);
DBUG_ASSERT(keylen == m_start_key.length);
DBUG_ASSERT(m_index_scan_type != partition_index_last);
if (!m_ordered_scan_ongoing)
DBUG_RETURN(handle_unordered_next(buf, TRUE));
DBUG_RETURN(handle_ordered_next(buf, TRUE));
}
/*
Read next record when performing index scan backwards
SYNOPSIS
index_prev()
buf Read row in MySQL Row Format
RETURN VALUE
>0 Error code
0 Success
DESCRIPTION
Used to read backwards through the index.
*/
int ha_partition::index_prev(uchar * buf)
{
DBUG_ENTER("ha_partition::index_prev");
decrement_statistics(&SSV::ha_read_prev_count);
/* TODO: read comment in index_next */
DBUG_ASSERT(m_index_scan_type != partition_index_first);
DBUG_RETURN(handle_ordered_prev(buf));
}
/*
Start a read of one range with start and end key
SYNOPSIS
read_range_first()
start_key Specification of start key
end_key Specification of end key
eq_range_arg Is it equal range
sorted Should records be returned in sorted order
RETURN VALUE
>0 Error code
0 Success
DESCRIPTION
We reimplement read_range_first since we don't want the compare_key
check at the end. This is already performed in the partition handler.
read_range_next is very much different due to that we need to scan
all underlying handlers.
*/
int ha_partition::read_range_first(const key_range *start_key,
const key_range *end_key,
bool eq_range_arg, bool sorted)
{
int error;
DBUG_ENTER("ha_partition::read_range_first");
m_ordered= sorted;
eq_range= eq_range_arg;
set_end_range(end_key);
range_key_part= m_curr_key_info[0]->key_part;
if (start_key)
m_start_key= *start_key;
else
m_start_key.key= NULL;
m_index_scan_type= partition_read_range;
error= common_index_read(m_rec0, MY_TEST(start_key));
DBUG_RETURN(error);
}
/*
Read next record in read of a range with start and end key
SYNOPSIS
read_range_next()
RETURN VALUE
>0 Error code
0 Success
*/
int ha_partition::read_range_next()
{
DBUG_ENTER("ha_partition::read_range_next");
if (m_ordered_scan_ongoing)
{
DBUG_RETURN(handle_ordered_next(table->record[0], eq_range));
}
DBUG_RETURN(handle_unordered_next(table->record[0], eq_range));
}
/*
Common routine to set up index scans
SYNOPSIS
ha_partition::partition_scan_set_up()
buf Buffer to later return record in (this function
needs it to calculate partitioning function
values)
idx_read_flag TRUE <=> m_start_key has range start endpoint which
probably can be used to determine the set of partitions
to scan.
FALSE <=> there is no start endpoint.
DESCRIPTION
Find out which partitions we'll need to read when scanning the specified
range.
If we need to scan only one partition, set m_ordered_scan_ongoing=FALSE
as we will not need to do merge ordering.
RETURN VALUE
>0 Error code
0 Success
*/
int ha_partition::partition_scan_set_up(uchar * buf, bool idx_read_flag)
{
DBUG_ENTER("ha_partition::partition_scan_set_up");
if (idx_read_flag)
get_partition_set(table,buf,active_index,&m_start_key,&m_part_spec);
else
{
m_part_spec.start_part= 0;
m_part_spec.end_part= m_tot_parts - 1;
}
if (m_part_spec.start_part > m_part_spec.end_part)
{
/*
We discovered a partition set but the set was empty so we report
key not found.
*/
DBUG_PRINT("info", ("scan with no partition to scan"));
DBUG_RETURN(HA_ERR_END_OF_FILE);
}
if (m_part_spec.start_part == m_part_spec.end_part)
{
/*
We discovered a single partition to scan, this never needs to be
performed using the ordered index scan.
*/
DBUG_PRINT("info", ("index scan using the single partition %d",
m_part_spec.start_part));
m_ordered_scan_ongoing= FALSE;
}
else
{
/*
Set m_ordered_scan_ongoing according how the scan should be done
Only exact partitions are discovered atm by get_partition_set.
Verify this, also bitmap must have at least one bit set otherwise
the result from this table is the empty set.
*/
uint start_part= bitmap_get_first_set(&(m_part_info->read_partitions));
if (start_part == MY_BIT_NONE)
{
DBUG_PRINT("info", ("scan with no partition to scan"));
DBUG_RETURN(HA_ERR_END_OF_FILE);
}
if (start_part > m_part_spec.start_part)
m_part_spec.start_part= start_part;
DBUG_ASSERT(m_part_spec.start_part < m_tot_parts);
m_ordered_scan_ongoing= m_ordered;
}
DBUG_ASSERT(m_part_spec.start_part < m_tot_parts);
DBUG_ASSERT(m_part_spec.end_part < m_tot_parts);
DBUG_RETURN(0);
}
/****************************************************************************
Unordered Index Scan Routines
****************************************************************************/
/*
Common routine to handle index_next with unordered results
SYNOPSIS
handle_unordered_next()
out:buf Read row in MySQL Row Format
next_same Called from index_next_same
RETURN VALUE
HA_ERR_END_OF_FILE End of scan
0 Success
other Error code
DESCRIPTION
These routines are used to scan partitions without considering order.
This is performed in two situations.
1) In read_multi_range this is the normal case
2) When performing any type of index_read, index_first, index_last where
all fields in the partition function is bound. In this case the index
scan is performed on only one partition and thus it isn't necessary to
perform any sort.
*/
int ha_partition::handle_unordered_next(uchar *buf, bool is_next_same)
{
handler *file;
int error;
DBUG_ENTER("ha_partition::handle_unordered_next");
if (m_part_spec.start_part >= m_tot_parts)
{
/* Should never happen! */
DBUG_ASSERT(0);
DBUG_RETURN(HA_ERR_END_OF_FILE);
}
file= m_file[m_part_spec.start_part];
/*
We should consider if this should be split into three functions as
partition_read_range is_next_same are always local constants
*/
if (m_index_scan_type == partition_read_range)
{
if (!(error= file->read_range_next()))
{
m_last_part= m_part_spec.start_part;
DBUG_RETURN(0);
}
}
else if (is_next_same)
{
if (!(error= file->ha_index_next_same(buf, m_start_key.key,
m_start_key.length)))
{
m_last_part= m_part_spec.start_part;
DBUG_RETURN(0);
}
}
else
{
if (!(error= file->ha_index_next(buf)))
{
m_last_part= m_part_spec.start_part;
DBUG_RETURN(0); // Row was in range
}
}
if (error == HA_ERR_END_OF_FILE)
{
m_part_spec.start_part++; // Start using next part
error= handle_unordered_scan_next_partition(buf);
}
DBUG_RETURN(error);
}
/*
Handle index_next when changing to new partition
SYNOPSIS
handle_unordered_scan_next_partition()
buf Read row in MySQL Row Format
RETURN VALUE
HA_ERR_END_OF_FILE End of scan
0 Success
other Error code
DESCRIPTION
This routine is used to start the index scan on the next partition.
Both initial start and after completing scan on one partition.
*/
int ha_partition::handle_unordered_scan_next_partition(uchar * buf)
{
uint i= m_part_spec.start_part;
int saved_error= HA_ERR_END_OF_FILE;
DBUG_ENTER("ha_partition::handle_unordered_scan_next_partition");
if (i)
i= bitmap_get_next_set(&m_part_info->read_partitions, i - 1);
else
i= bitmap_get_first_set(&m_part_info->read_partitions);
for (;
i <= m_part_spec.end_part;
i= bitmap_get_next_set(&m_part_info->read_partitions, i))
{
int error;
handler *file= m_file[i];
m_part_spec.start_part= i;
switch (m_index_scan_type) {
case partition_read_range:
DBUG_PRINT("info", ("read_range_first on partition %d", i));
error= file->read_range_first(m_start_key.key? &m_start_key: NULL,
end_range, eq_range, FALSE);
break;
case partition_index_read:
DBUG_PRINT("info", ("index_read on partition %d", i));
error= file->ha_index_read_map(buf, m_start_key.key,
m_start_key.keypart_map,
m_start_key.flag);
break;
case partition_index_first:
DBUG_PRINT("info", ("index_first on partition %d", i));
error= file->ha_index_first(buf);
break;
case partition_index_first_unordered:
/*
We perform a scan without sorting and this means that we
should not use the index_first since not all handlers
support it and it is also unnecessary to restrict sort
order.
*/
DBUG_PRINT("info", ("read_range_first on partition %d", i));
table->record[0]= buf;
error= file->read_range_first(0, end_range, eq_range, 0);
table->record[0]= m_rec0;
break;
default:
DBUG_ASSERT(FALSE);
DBUG_RETURN(1);
}
if (!error)
{
m_last_part= i;
DBUG_RETURN(0);
}
if ((error != HA_ERR_END_OF_FILE) && (error != HA_ERR_KEY_NOT_FOUND))
DBUG_RETURN(error);
/*
If HA_ERR_KEY_NOT_FOUND, we must return that error instead of
HA_ERR_END_OF_FILE, to be able to continue search.
*/
if (saved_error != HA_ERR_KEY_NOT_FOUND)
saved_error= error;
DBUG_PRINT("info", ("END_OF_FILE/KEY_NOT_FOUND on partition %d", i));
}
if (saved_error == HA_ERR_END_OF_FILE)
m_part_spec.start_part= NO_CURRENT_PART_ID;
DBUG_RETURN(saved_error);
}
/**
Common routine to start index scan with ordered results.
@param[out] buf Read row in MySQL Row Format
@return Operation status
@retval HA_ERR_END_OF_FILE End of scan
@retval HA_ERR_KEY_NOT_FOUNE End of scan
@retval 0 Success
@retval other Error code
@details
This part contains the logic to handle index scans that require ordered
output. This includes all except those started by read_range_first with
the flag ordered set to FALSE. Thus most direct index_read and all
index_first and index_last.
We implement ordering by keeping one record plus a key buffer for each
partition. Every time a new entry is requested we will fetch a new
entry from the partition that is currently not filled with an entry.
Then the entry is put into its proper sort position.
Returning a record is done by getting the top record, copying the
record to the request buffer and setting the partition as empty on
entries.
*/
int ha_partition::handle_ordered_index_scan(uchar *buf, bool reverse_order)
{
uint i;
uint j= queue_first_element(&m_queue);
bool found= FALSE;
uchar *part_rec_buf_ptr= m_ordered_rec_buffer;
int saved_error= HA_ERR_END_OF_FILE;
DBUG_ENTER("ha_partition::handle_ordered_index_scan");
if (m_key_not_found)
{
m_key_not_found= false;
bitmap_clear_all(&m_key_not_found_partitions);
}
m_top_entry= NO_CURRENT_PART_ID;
queue_remove_all(&m_queue);
DBUG_ASSERT(bitmap_is_set(&m_part_info->read_partitions,
m_part_spec.start_part));
/*
Position part_rec_buf_ptr to point to the first used partition >=
start_part. There may be partitions marked by used_partitions,
but is before start_part. These partitions has allocated record buffers
but is dynamically pruned, so those buffers must be skipped.
*/
for (i= bitmap_get_first_set(&m_part_info->read_partitions);
i < m_part_spec.start_part;
i= bitmap_get_next_set(&m_part_info->read_partitions, i))
{
part_rec_buf_ptr+= m_priority_queue_rec_len;
}
DBUG_PRINT("info", ("m_part_spec.start_part %u first_used_part %u",
m_part_spec.start_part, i));
for (/* continue from above */ ;
i <= m_part_spec.end_part;
i= bitmap_get_next_set(&m_part_info->read_partitions, i))
{
DBUG_PRINT("info", ("reading from part %u (scan_type: %u)",
i, m_index_scan_type));
DBUG_ASSERT(i == uint2korr(part_rec_buf_ptr));
uchar *rec_buf_ptr= part_rec_buf_ptr + PARTITION_BYTES_IN_POS;
int error;
handler *file= m_file[i];
switch (m_index_scan_type) {
case partition_index_read:
error= file->ha_index_read_map(rec_buf_ptr,
m_start_key.key,
m_start_key.keypart_map,
m_start_key.flag);
break;
case partition_index_first:
error= file->ha_index_first(rec_buf_ptr);
reverse_order= FALSE;
break;
case partition_index_last:
error= file->ha_index_last(rec_buf_ptr);
reverse_order= TRUE;
break;
case partition_read_range:
{
/*
This can only read record to table->record[0], as it was set when
the table was being opened. We have to memcpy data ourselves.
*/
error= file->read_range_first(m_start_key.key? &m_start_key: NULL,
end_range, eq_range, TRUE);
memcpy(rec_buf_ptr, table->record[0], m_rec_length);
reverse_order= FALSE;
break;
}
default:
DBUG_ASSERT(FALSE);
DBUG_RETURN(HA_ERR_END_OF_FILE);
}
if (!error)
{
found= TRUE;
if (!m_using_extended_keys)
{
file->position(rec_buf_ptr);
memcpy(rec_buf_ptr + m_rec_length, file->ref, file->ref_length);
}
/*
Initialize queue without order first, simply insert
*/
queue_element(&m_queue, j++)= part_rec_buf_ptr;
}
else if (error != HA_ERR_KEY_NOT_FOUND && error != HA_ERR_END_OF_FILE)
{
DBUG_RETURN(error);
}
else if (error == HA_ERR_KEY_NOT_FOUND)
{
DBUG_PRINT("info", ("HA_ERR_KEY_NOT_FOUND from partition %u", i));
bitmap_set_bit(&m_key_not_found_partitions, i);
m_key_not_found= true;
saved_error= error;
}
part_rec_buf_ptr+= m_priority_queue_rec_len;
}
if (found)
{
/*
We found at least one partition with data, now sort all entries and
after that read the first entry and copy it to the buffer to return in.
*/
queue_set_max_at_top(&m_queue, reverse_order);
queue_set_cmp_arg(&m_queue, m_using_extended_keys? m_curr_key_info : (void*)this);
m_queue.elements= j - queue_first_element(&m_queue);
queue_fix(&m_queue);
return_top_record(buf);
table->status= 0;
DBUG_PRINT("info", ("Record returned from partition %d", m_top_entry));
DBUG_RETURN(0);
}
DBUG_RETURN(saved_error);
}
/*
Return the top record in sort order
SYNOPSIS
return_top_record()
out:buf Row returned in MySQL Row Format
RETURN VALUE
NONE
*/
void ha_partition::return_top_record(uchar *buf)
{
uint part_id;
uchar *key_buffer= queue_top(&m_queue);
uchar *rec_buffer= key_buffer + PARTITION_BYTES_IN_POS;
part_id= uint2korr(key_buffer);
memcpy(buf, rec_buffer, m_rec_length);
m_last_part= part_id;
m_top_entry= part_id;
}
/**
Add index_next/prev from partitions without exact match.
If there where any partitions that returned HA_ERR_KEY_NOT_FOUND when
ha_index_read_map was done, those partitions must be included in the
following index_next/prev call.
*/
int ha_partition::handle_ordered_index_scan_key_not_found()
{
int error;
uint i, old_elements= m_queue.elements;
uchar *part_buf= m_ordered_rec_buffer;
uchar *curr_rec_buf= NULL;
DBUG_ENTER("ha_partition::handle_ordered_index_scan_key_not_found");
DBUG_ASSERT(m_key_not_found);
/*
Loop over all used partitions to get the correct offset
into m_ordered_rec_buffer.
*/
for (i= bitmap_get_first_set(&m_part_info->read_partitions);
i < m_tot_parts;
i= bitmap_get_next_set(&m_part_info->read_partitions, i))
{
if (bitmap_is_set(&m_key_not_found_partitions, i))
{
/*
This partition is used and did return HA_ERR_KEY_NOT_FOUND
in index_read_map.
*/
curr_rec_buf= part_buf + PARTITION_BYTES_IN_POS;
error= m_file[i]->ha_index_next(curr_rec_buf);
/* HA_ERR_KEY_NOT_FOUND is not allowed from index_next! */
DBUG_ASSERT(error != HA_ERR_KEY_NOT_FOUND);
if (!error)
queue_insert(&m_queue, part_buf);
else if (error != HA_ERR_END_OF_FILE && error != HA_ERR_KEY_NOT_FOUND)
DBUG_RETURN(error);
}
part_buf += m_priority_queue_rec_len;
}
DBUG_ASSERT(curr_rec_buf);
bitmap_clear_all(&m_key_not_found_partitions);
m_key_not_found= false;
if (m_queue.elements > old_elements)
{
/* Update m_top_entry, which may have changed. */
uchar *key_buffer= queue_top(&m_queue);
m_top_entry= uint2korr(key_buffer);
}
DBUG_RETURN(0);
}
/*
Common routine to handle index_next with ordered results
SYNOPSIS
handle_ordered_next()
out:buf Read row in MySQL Row Format
next_same Called from index_next_same
RETURN VALUE
HA_ERR_END_OF_FILE End of scan
0 Success
other Error code
*/
int ha_partition::handle_ordered_next(uchar *buf, bool is_next_same)
{
int error;
uint part_id= m_top_entry;
uchar *rec_buf= queue_top(&m_queue) + PARTITION_BYTES_IN_POS;
handler *file;
DBUG_ENTER("ha_partition::handle_ordered_next");
if (m_key_not_found)
{
if (is_next_same)
{
/* Only rows which match the key. */
m_key_not_found= false;
bitmap_clear_all(&m_key_not_found_partitions);
}
else
{
/* There are partitions not included in the index record queue. */
uint old_elements= m_queue.elements;
if ((error= handle_ordered_index_scan_key_not_found()))
DBUG_RETURN(error);
/*
If the queue top changed, i.e. one of the partitions that gave
HA_ERR_KEY_NOT_FOUND in index_read_map found the next record,
return it.
Otherwise replace the old with a call to index_next (fall through).
*/
if (old_elements != m_queue.elements && part_id != m_top_entry)
{
return_top_record(buf);
DBUG_RETURN(0);
}
}
}
if (part_id >= m_tot_parts)
{
/* This should never happen! */
DBUG_ASSERT(0);
DBUG_RETURN(HA_ERR_END_OF_FILE);
}
file= m_file[part_id];
if (m_index_scan_type == partition_read_range)
{
error= file->read_range_next();
memcpy(rec_buf, table->record[0], m_rec_length);
}
else if (!is_next_same)
error= file->ha_index_next(rec_buf);
else
error= file->ha_index_next_same(rec_buf, m_start_key.key,
m_start_key.length);
if (error)
{
if (error == HA_ERR_END_OF_FILE)
{
/* Return next buffered row */
queue_remove_top(&m_queue);
if (m_queue.elements)
{
DBUG_PRINT("info", ("Record returned from partition %u (2)",
m_top_entry));
return_top_record(buf);
table->status= 0;
error= 0;
}
}
DBUG_RETURN(error);
}
if (!m_using_extended_keys)
{
file->position(rec_buf);
memcpy(rec_buf + m_rec_length, file->ref, file->ref_length);
}
queue_replace_top(&m_queue);
return_top_record(buf);
DBUG_PRINT("info", ("Record returned from partition %u", m_top_entry));
DBUG_RETURN(0);
}
/*
Common routine to handle index_prev with ordered results
SYNOPSIS
handle_ordered_prev()
out:buf Read row in MySQL Row Format
RETURN VALUE
HA_ERR_END_OF_FILE End of scan
0 Success
other Error code
*/
int ha_partition::handle_ordered_prev(uchar *buf)
{
int error;
uint part_id= m_top_entry;
uchar *rec_buf= queue_top(&m_queue) + PARTITION_BYTES_IN_POS;
handler *file= m_file[part_id];
DBUG_ENTER("ha_partition::handle_ordered_prev");
if ((error= file->ha_index_prev(rec_buf)))
{
if (error == HA_ERR_END_OF_FILE)
{
queue_remove_top(&m_queue);
if (m_queue.elements)
{
return_top_record(buf);
DBUG_PRINT("info", ("Record returned from partition %d (2)",
m_top_entry));
error= 0;
table->status= 0;
}
}
DBUG_RETURN(error);
}
queue_replace_top(&m_queue);
return_top_record(buf);
DBUG_PRINT("info", ("Record returned from partition %d", m_top_entry));
DBUG_RETURN(0);
}
/****************************************************************************
MODULE information calls
****************************************************************************/
/*
These are all first approximations of the extra, info, scan_time
and read_time calls
*/
/**
Helper function for sorting according to number of rows in descending order.
*/
int ha_partition::compare_number_of_records(ha_partition *me,
const uint32 *a,
const uint32 *b)
{
handler **file= me->m_file;
/* Note: sorting in descending order! */
if (file[*a]->stats.records > file[*b]->stats.records)
return -1;
if (file[*a]->stats.records < file[*b]->stats.records)
return 1;
return 0;
}
/*
General method to gather info from handler
SYNOPSIS
info()
flag Specifies what info is requested
RETURN VALUE
NONE
DESCRIPTION
::info() is used to return information to the optimizer.
Currently this table handler doesn't implement most of the fields
really needed. SHOW also makes use of this data
Another note, if your handler doesn't proved exact record count,
you will probably want to have the following in your code:
if (records < 2)
records = 2;
The reason is that the server will optimize for cases of only a single
record. If in a table scan you don't know the number of records
it will probably be better to set records to two so you can return
as many records as you need.
Along with records a few more variables you may wish to set are:
records
deleted
data_file_length
index_file_length
delete_length
check_time
Take a look at the public variables in handler.h for more information.
Called in:
filesort.cc
ha_heap.cc
item_sum.cc
opt_sum.cc
sql_delete.cc
sql_delete.cc
sql_derived.cc
sql_select.cc
sql_select.cc
sql_select.cc
sql_select.cc
sql_select.cc
sql_show.cc
sql_show.cc
sql_show.cc
sql_show.cc
sql_table.cc
sql_union.cc
sql_update.cc
Some flags that are not implemented
HA_STATUS_POS:
This parameter is never used from the MySQL Server. It is checked in a
place in MyISAM so could potentially be used by MyISAM specific
programs.
HA_STATUS_NO_LOCK:
This is declared and often used. It's only used by MyISAM.
It means that MySQL doesn't need the absolute latest statistics
information. This may save the handler from doing internal locks while
retrieving statistics data.
*/
int ha_partition::info(uint flag)
{
uint no_lock_flag= flag & HA_STATUS_NO_LOCK;
uint extra_var_flag= flag & HA_STATUS_VARIABLE_EXTRA;
DBUG_ENTER("ha_partition::info");
#ifndef DBUG_OFF
if (bitmap_is_set_all(&(m_part_info->read_partitions)))
DBUG_PRINT("info", ("All partitions are used"));
#endif /* DBUG_OFF */
if (flag & HA_STATUS_AUTO)
{
bool auto_inc_is_first_in_idx= (table_share->next_number_keypart == 0);
DBUG_PRINT("info", ("HA_STATUS_AUTO"));
if (!table->found_next_number_field)
stats.auto_increment_value= 0;
else if (part_share->auto_inc_initialized)
{
lock_auto_increment();
stats.auto_increment_value= part_share->next_auto_inc_val;
unlock_auto_increment();
}
else
{
lock_auto_increment();
/* to avoid two concurrent initializations, check again when locked */
if (part_share->auto_inc_initialized)
stats.auto_increment_value= part_share->next_auto_inc_val;
else
{
/*
The auto-inc mutex in the table_share is locked, so we do not need
to have the handlers locked.
HA_STATUS_NO_LOCK is not checked, since we cannot skip locking
the mutex, because it is initialized.
*/
handler *file, **file_array;
ulonglong auto_increment_value= 0;
file_array= m_file;
DBUG_PRINT("info",
("checking all partitions for auto_increment_value"));
do
{
file= *file_array;
file->info(HA_STATUS_AUTO | no_lock_flag);
set_if_bigger(auto_increment_value,
file->stats.auto_increment_value);
} while (*(++file_array));
DBUG_ASSERT(auto_increment_value);
stats.auto_increment_value= auto_increment_value;
if (auto_inc_is_first_in_idx)
{
set_if_bigger(part_share->next_auto_inc_val,
auto_increment_value);
part_share->auto_inc_initialized= true;
DBUG_PRINT("info", ("initializing next_auto_inc_val to %lu",
(ulong) part_share->next_auto_inc_val));
}
}
unlock_auto_increment();
}
}
if (flag & HA_STATUS_VARIABLE)
{
uint i;
DBUG_PRINT("info", ("HA_STATUS_VARIABLE"));
/*
Calculates statistical variables
records: Estimate of number records in table
We report sum (always at least 2 if not empty)
deleted: Estimate of number holes in the table due to
deletes
We report sum
data_file_length: Length of data file, in principle bytes in table
We report sum
index_file_length: Length of index file, in principle bytes in
indexes in the table
We report sum
delete_length: Length of free space easily used by new records in table
We report sum
mean_record_length:Mean record length in the table
We calculate this
check_time: Time of last check (only applicable to MyISAM)
We report last time of all underlying handlers
*/
handler *file;
stats.records= 0;
stats.deleted= 0;
stats.data_file_length= 0;
stats.index_file_length= 0;
stats.check_time= 0;
stats.delete_length= 0;
for (i= bitmap_get_first_set(&m_part_info->read_partitions);
i < m_tot_parts;
i= bitmap_get_next_set(&m_part_info->read_partitions, i))
{
file= m_file[i];
file->info(HA_STATUS_VARIABLE | no_lock_flag | extra_var_flag);
stats.records+= file->stats.records;
stats.deleted+= file->stats.deleted;
stats.data_file_length+= file->stats.data_file_length;
stats.index_file_length+= file->stats.index_file_length;
stats.delete_length+= file->stats.delete_length;
if (file->stats.check_time > stats.check_time)
stats.check_time= file->stats.check_time;
}
if (stats.records && stats.records < 2 &&
!(m_file[0]->ha_table_flags() & HA_STATS_RECORDS_IS_EXACT))
stats.records= 2;
if (stats.records > 0)
stats.mean_rec_length= (ulong) (stats.data_file_length / stats.records);
else
stats.mean_rec_length= 0;
}
if (flag & HA_STATUS_CONST)
{
DBUG_PRINT("info", ("HA_STATUS_CONST"));
/*
Recalculate loads of constant variables. MyISAM also sets things
directly on the table share object.
Check whether this should be fixed since handlers should not
change things directly on the table object.
Monty comment: This should NOT be changed! It's the handlers
responsibility to correct table->s->keys_xxxx information if keys
have been disabled.
The most important parameters set here is records per key on
all indexes. block_size and primar key ref_length.
For each index there is an array of rec_per_key.
As an example if we have an index with three attributes a,b and c
we will have an array of 3 rec_per_key.
rec_per_key[0] is an estimate of number of records divided by
number of unique values of the field a.
rec_per_key[1] is an estimate of the number of records divided
by the number of unique combinations of the fields a and b.
rec_per_key[2] is an estimate of the number of records divided
by the number of unique combinations of the fields a,b and c.
Many handlers only set the value of rec_per_key when all fields
are bound (rec_per_key[2] in the example above).
If the handler doesn't support statistics, it should set all of the
above to 0.
We first scans through all partitions to get the one holding most rows.
We will then allow the handler with the most rows to set
the rec_per_key and use this as an estimate on the total table.
max_data_file_length: Maximum data file length
We ignore it, is only used in
SHOW TABLE STATUS
max_index_file_length: Maximum index file length
We ignore it since it is never used
block_size: Block size used
We set it to the value of the first handler
ref_length: We set this to the value calculated
and stored in local object
create_time: Creation time of table
So we calculate these constants by using the variables from the
handler with most rows.
*/
handler *file, **file_array;
ulonglong max_records= 0;
uint32 i= 0;
uint32 handler_instance= 0;
file_array= m_file;
do
{
file= *file_array;
/* Get variables if not already done */
if (!(flag & HA_STATUS_VARIABLE) ||
!bitmap_is_set(&(m_part_info->read_partitions),
(uint)(file_array - m_file)))
file->info(HA_STATUS_VARIABLE | no_lock_flag | extra_var_flag);
if (file->stats.records > max_records)
{
max_records= file->stats.records;
handler_instance= i;
}
i++;
} while (*(++file_array));
/*
Sort the array of part_ids by number of records in
in descending order.
*/
my_qsort2((void*) m_part_ids_sorted_by_num_of_records,
m_tot_parts,
sizeof(uint32),
(qsort2_cmp) compare_number_of_records,
this);
file= m_file[handler_instance];
file->info(HA_STATUS_CONST | no_lock_flag);
stats.block_size= file->stats.block_size;
stats.create_time= file->stats.create_time;
ref_length= m_ref_length;
}
if (flag & HA_STATUS_ERRKEY)
{
handler *file= m_file[m_last_part];
DBUG_PRINT("info", ("info: HA_STATUS_ERRKEY"));
/*
This flag is used to get index number of the unique index that
reported duplicate key
We will report the errkey on the last handler used and ignore the rest
Note: all engines does not support HA_STATUS_ERRKEY, so set errkey.
*/
file->errkey= errkey;
file->info(HA_STATUS_ERRKEY | no_lock_flag);
errkey= file->errkey;
}
if (flag & HA_STATUS_TIME)
{
handler *file, **file_array;
DBUG_PRINT("info", ("info: HA_STATUS_TIME"));
/*
This flag is used to set the latest update time of the table.
Used by SHOW commands
We will report the maximum of these times
*/
stats.update_time= 0;
file_array= m_file;
do
{
file= *file_array;
file->info(HA_STATUS_TIME | no_lock_flag);
if (file->stats.update_time > stats.update_time)
stats.update_time= file->stats.update_time;
} while (*(++file_array));
}
DBUG_RETURN(0);
}
void ha_partition::get_dynamic_partition_info(PARTITION_STATS *stat_info,
uint part_id)
{
handler *file= m_file[part_id];
DBUG_ASSERT(bitmap_is_set(&(m_part_info->read_partitions), part_id));
file->info(HA_STATUS_TIME | HA_STATUS_VARIABLE |
HA_STATUS_VARIABLE_EXTRA | HA_STATUS_NO_LOCK);
stat_info->records= file->stats.records;
stat_info->mean_rec_length= file->stats.mean_rec_length;
stat_info->data_file_length= file->stats.data_file_length;
stat_info->max_data_file_length= file->stats.max_data_file_length;
stat_info->index_file_length= file->stats.index_file_length;
stat_info->delete_length= file->stats.delete_length;
stat_info->create_time= file->stats.create_time;
stat_info->update_time= file->stats.update_time;
stat_info->check_time= file->stats.check_time;
stat_info->check_sum= 0;
if (file->ha_table_flags() & (HA_HAS_OLD_CHECKSUM | HA_HAS_NEW_CHECKSUM))
stat_info->check_sum= file->checksum();
return;
}
static int extra_cb(handler *h, void *operation)
{
return h->extra(*(enum ha_extra_function*)operation);
}
static int start_keyread_cb(handler* h, void *p)
{
return h->ha_start_keyread(*(uint*)p);
}
static int end_keyread_cb(handler* h, void *unused)
{
return h->ha_end_keyread();
}
/**
General function to prepare handler for certain behavior.
@param[in] operation operation to execute
@return status
@retval 0 success
@retval >0 error code
@detail
extra() is called whenever the server wishes to send a hint to
the storage engine. The MyISAM engine implements the most hints.
We divide the parameters into the following categories:
1) Operations used by most handlers
2) Operations used by some non-MyISAM handlers
3) Operations used only by MyISAM
4) Operations only used by temporary tables for query processing
5) Operations only used by MyISAM internally
6) Operations not used at all
7) Operations only used by federated tables for query processing
8) Operations only used by NDB
9) Operations only used by MERGE
The partition handler need to handle category 1), 2) and 3).
1) Operations used by most handlers
-----------------------------------
HA_EXTRA_RESET:
This option is used by most handlers and it resets the handler state
to the same state as after an open call. This includes releasing
any READ CACHE or WRITE CACHE or other internal buffer used.
It is called from the reset method in the handler interface. There are
three instances where this is called.
1) After completing a INSERT ... SELECT ... query the handler for the
table inserted into is reset
2) It is called from close_thread_table which in turn is called from
close_thread_tables except in the case where the tables are locked
in which case ha_commit_stmt is called instead.
It is only called from here if refresh_version hasn't changed and the
table is not an old table when calling close_thread_table.
close_thread_tables is called from many places as a general clean up
function after completing a query.
3) It is called when deleting the QUICK_RANGE_SELECT object if the
QUICK_RANGE_SELECT object had its own handler object. It is called
immediately before close of this local handler object.
HA_EXTRA_KEYREAD:
HA_EXTRA_NO_KEYREAD:
These parameters are used to provide an optimisation hint to the handler.
If HA_EXTRA_KEYREAD is set it is enough to read the index fields, for
many handlers this means that the index-only scans can be used and it
is not necessary to use the real records to satisfy this part of the
query. Index-only scans is a very important optimisation for disk-based
indexes. For main-memory indexes most indexes contain a reference to the
record and thus KEYREAD only says that it is enough to read key fields.
HA_EXTRA_NO_KEYREAD disables this for the handler, also HA_EXTRA_RESET
will disable this option.
The handler will set HA_KEYREAD_ONLY in its table flags to indicate this
feature is supported.
HA_EXTRA_FLUSH:
Indication to flush tables to disk, is supposed to be used to
ensure disk based tables are flushed at end of query execution.
Currently is never used.
HA_EXTRA_FORCE_REOPEN:
Only used by MyISAM and Archive, called when altering table,
closing tables to enforce a reopen of the table files.
2) Operations used by some non-MyISAM handlers
----------------------------------------------
HA_EXTRA_KEYREAD_PRESERVE_FIELDS:
This is a strictly InnoDB feature that is more or less undocumented.
When it is activated InnoDB copies field by field from its fetch
cache instead of all fields in one memcpy. Have no idea what the
purpose of this is.
Cut from include/my_base.h:
When using HA_EXTRA_KEYREAD, overwrite only key member fields and keep
other fields intact. When this is off (by default) InnoDB will use memcpy
to overwrite entire row.
HA_EXTRA_IGNORE_DUP_KEY:
HA_EXTRA_NO_IGNORE_DUP_KEY:
Informs the handler to we will not stop the transaction if we get an
duplicate key errors during insert/update.
Always called in pair, triggered by INSERT IGNORE and other similar
SQL constructs.
Not used by MyISAM.
3) Operations used only by MyISAM
---------------------------------
HA_EXTRA_NORMAL:
Only used in MyISAM to reset quick mode, not implemented by any other
handler. Quick mode is also reset in MyISAM by HA_EXTRA_RESET.
It is called after completing a successful DELETE query if the QUICK
option is set.
HA_EXTRA_QUICK:
When the user does DELETE QUICK FROM table where-clause; this extra
option is called before the delete query is performed and
HA_EXTRA_NORMAL is called after the delete query is completed.
Temporary tables used internally in MySQL always set this option
The meaning of quick mode is that when deleting in a B-tree no merging
of leafs is performed. This is a common method and many large DBMS's
actually only support this quick mode since it is very difficult to
merge leaves in a tree used by many threads concurrently.
HA_EXTRA_CACHE:
This flag is usually set with extra_opt along with a cache size.
The size of this buffer is set by the user variable
record_buffer_size. The value of this cache size is the amount of
data read from disk in each fetch when performing a table scan.
This means that before scanning a table it is normal to call
extra with HA_EXTRA_CACHE and when the scan is completed to call
HA_EXTRA_NO_CACHE to release the cache memory.
Some special care is taken when using this extra parameter since there
could be a write ongoing on the table in the same statement. In this
one has to take special care since there might be a WRITE CACHE as
well. HA_EXTRA_CACHE specifies using a READ CACHE and using
READ CACHE and WRITE CACHE at the same time is not possible.
Only MyISAM currently use this option.
It is set when doing full table scans using rr_sequential and
reset when completing such a scan with end_read_record
(resetting means calling extra with HA_EXTRA_NO_CACHE).
It is set in filesort.cc for MyISAM internal tables and it is set in
a multi-update where HA_EXTRA_CACHE is called on a temporary result
table and after that ha_rnd_init(0) on table to be updated
and immediately after that HA_EXTRA_NO_CACHE on table to be updated.
Apart from that it is always used from init_read_record but not when
used from UPDATE statements. It is not used from DELETE statements
with ORDER BY and LIMIT but it is used in normal scan loop in DELETE
statements. The reason here is that DELETE's in MyISAM doesn't move
existings data rows.
It is also set in copy_data_between_tables when scanning the old table
to copy over to the new table.
And it is set in join_init_read_record where quick objects are used
to perform a scan on the table. In this case the full table scan can
even be performed multiple times as part of the nested loop join.
For purposes of the partition handler it is obviously necessary to have
special treatment of this extra call. If we would simply pass this
extra call down to each handler we would allocate
cache size * no of partitions amount of memory and this is not
necessary since we will only scan one partition at a time when doing
full table scans.
Thus we treat it by first checking whether we have MyISAM handlers in
the table, if not we simply ignore the call and if we have we will
record the call but will not call any underlying handler yet. Then
when performing the sequential scan we will check this recorded value
and call extra_opt whenever we start scanning a new partition.
HA_EXTRA_NO_CACHE:
When performing a UNION SELECT HA_EXTRA_NO_CACHE is called from the
flush method in the select_union class.
It is used to some extent when insert delayed inserts.
See HA_EXTRA_RESET_STATE for use in conjunction with delete_all_rows().
It should be ok to call HA_EXTRA_NO_CACHE on all underlying handlers
if they are MyISAM handlers. Other handlers we can ignore the call
for. If no cache is in use they will quickly return after finding
this out. And we also ensure that all caches are disabled and no one
is left by mistake.
In the future this call will probably be deleted and we will instead call
::reset();
HA_EXTRA_WRITE_CACHE:
See above, called from various places. It is mostly used when we
do INSERT ... SELECT
No special handling to save cache space is developed currently.
HA_EXTRA_PREPARE_FOR_UPDATE:
This is called as part of a multi-table update. When the table to be
updated is also scanned then this informs MyISAM handler to drop any
caches if dynamic records are used (fixed size records do not care
about this call). We pass this along to the first partition to scan, and
flag that it is to be called after HA_EXTRA_CACHE when moving to the next
partition to scan.
HA_EXTRA_PREPARE_FOR_DROP:
Only used by MyISAM, called in preparation for a DROP TABLE.
It's used mostly by Windows that cannot handle dropping an open file.
On other platforms it has the same effect as HA_EXTRA_FORCE_REOPEN.
HA_EXTRA_PREPARE_FOR_RENAME:
Informs the handler we are about to attempt a rename of the table.
For handlers that have share open files (MyISAM key-file and
Archive writer) they must close the files before rename is possible
on Windows.
HA_EXTRA_READCHECK:
HA_EXTRA_NO_READCHECK:
Only one call to HA_EXTRA_NO_READCHECK from ha_open where it says that
this is not needed in SQL. The reason for this call is that MyISAM sets
the READ_CHECK_USED in the open call so the call is needed for MyISAM
to reset this feature.
The idea with this parameter was to inform of doing/not doing a read
check before applying an update. Since SQL always performs a read before
applying the update No Read Check is needed in MyISAM as well.
This is a cut from Docs/myisam.txt
Sometimes you might want to force an update without checking whether
another user has changed the record since you last read it. This is
somewhat dangerous, so it should ideally not be used. That can be
accomplished by wrapping the mi_update() call in two calls to mi_extra(),
using these functions:
HA_EXTRA_NO_READCHECK=5 No readcheck on update
HA_EXTRA_READCHECK=6 Use readcheck (def)
4) Operations only used by temporary tables for query processing
----------------------------------------------------------------
HA_EXTRA_RESET_STATE:
Same as reset() except that buffers are not released. If there is
a READ CACHE it is reinit'ed. A cache is reinit'ed to restart reading
or to change type of cache between READ CACHE and WRITE CACHE.
This extra function is always called immediately before calling
delete_all_rows on the handler for temporary tables.
There are cases however when HA_EXTRA_RESET_STATE isn't called in
a similar case for a temporary table in sql_union.cc and in two other
cases HA_EXTRA_NO_CACHE is called before and HA_EXTRA_WRITE_CACHE
called afterwards.
The case with HA_EXTRA_NO_CACHE and HA_EXTRA_WRITE_CACHE means
disable caching, delete all rows and enable WRITE CACHE. This is
used for temporary tables containing distinct sums and a
functional group.
The only case that delete_all_rows is called on non-temporary tables
is in sql_delete.cc when DELETE FROM table; is called by a user.
In this case no special extra calls are performed before or after this
call.
The partition handler should not need to bother about this one. It
should never be called.
HA_EXTRA_NO_ROWS:
Don't insert rows indication to HEAP and MyISAM, only used by temporary
tables used in query processing.
Not handled by partition handler.
5) Operations only used by MyISAM internally
--------------------------------------------
HA_EXTRA_REINIT_CACHE:
This call reinitializes the READ CACHE described above if there is one
and otherwise the call is ignored.
We can thus safely call it on all underlying handlers if they are
MyISAM handlers. It is however never called so we don't handle it at all.
HA_EXTRA_FLUSH_CACHE:
Flush WRITE CACHE in MyISAM. It is only from one place in the code.
This is in sql_insert.cc where it is called if the table_flags doesn't
contain HA_DUPLICATE_POS. The only handler having the HA_DUPLICATE_POS
set is the MyISAM handler and so the only handler not receiving this
call is MyISAM.
Thus in effect this call is called but never used. Could be removed
from sql_insert.cc
HA_EXTRA_NO_USER_CHANGE:
Only used by MyISAM, never called.
Simulates lock_type as locked.
HA_EXTRA_WAIT_LOCK:
HA_EXTRA_WAIT_NOLOCK:
Only used by MyISAM, called from MyISAM handler but never from server
code on top of the handler.
Sets lock_wait on/off
HA_EXTRA_NO_KEYS:
Only used MyISAM, only used internally in MyISAM handler, never called
from server level.
HA_EXTRA_KEYREAD_CHANGE_POS:
HA_EXTRA_REMEMBER_POS:
HA_EXTRA_RESTORE_POS:
HA_EXTRA_PRELOAD_BUFFER_SIZE:
HA_EXTRA_CHANGE_KEY_TO_DUP:
HA_EXTRA_CHANGE_KEY_TO_UNIQUE:
Only used by MyISAM, never called.
6) Operations not used at all
-----------------------------
HA_EXTRA_KEY_CACHE:
HA_EXTRA_NO_KEY_CACHE:
This parameters are no longer used and could be removed.
7) Operations only used by federated tables for query processing
----------------------------------------------------------------
HA_EXTRA_INSERT_WITH_UPDATE:
Inform handler that an "INSERT...ON DUPLICATE KEY UPDATE" will be
executed. This condition is unset by HA_EXTRA_NO_IGNORE_DUP_KEY.
8) Operations only used by NDB
------------------------------
HA_EXTRA_DELETE_CANNOT_BATCH:
HA_EXTRA_UPDATE_CANNOT_BATCH:
Inform handler that delete_row()/update_row() cannot batch deletes/updates
and should perform them immediately. This may be needed when table has
AFTER DELETE/UPDATE triggers which access to subject table.
These flags are reset by the handler::extra(HA_EXTRA_RESET) call.
9) Operations only used by MERGE
------------------------------
HA_EXTRA_ADD_CHILDREN_LIST:
HA_EXTRA_ATTACH_CHILDREN:
HA_EXTRA_IS_ATTACHED_CHILDREN:
HA_EXTRA_DETACH_CHILDREN:
Special actions for MERGE tables. Ignore.
*/
int ha_partition::extra(enum ha_extra_function operation)
{
DBUG_ENTER("ha_partition:extra");
DBUG_PRINT("info", ("operation: %d", (int) operation));
switch (operation) {
/* Category 1), used by most handlers */
case HA_EXTRA_NO_KEYREAD:
DBUG_RETURN(loop_partitions(end_keyread_cb, NULL));
case HA_EXTRA_KEYREAD:
case HA_EXTRA_FLUSH:
case HA_EXTRA_PREPARE_FOR_FORCED_CLOSE:
DBUG_RETURN(loop_partitions(extra_cb, &operation));
case HA_EXTRA_PREPARE_FOR_RENAME:
case HA_EXTRA_FORCE_REOPEN:
DBUG_RETURN(loop_extra_alter(operation));
break;
/* Category 2), used by non-MyISAM handlers */
case HA_EXTRA_IGNORE_DUP_KEY:
case HA_EXTRA_NO_IGNORE_DUP_KEY:
case HA_EXTRA_KEYREAD_PRESERVE_FIELDS:
{
if (!m_myisam)
DBUG_RETURN(loop_partitions(extra_cb, &operation));
break;
}
/* Category 3), used by MyISAM handlers */
case HA_EXTRA_PREPARE_FOR_UPDATE:
/*
Needs to be run on the first partition in the range now, and
later in late_extra_cache, when switching to a new partition to scan.
*/
m_extra_prepare_for_update= TRUE;
if (m_part_spec.start_part != NO_CURRENT_PART_ID)
{
if (!m_extra_cache)
m_extra_cache_part_id= m_part_spec.start_part;
DBUG_ASSERT(m_extra_cache_part_id == m_part_spec.start_part);
(void) m_file[m_part_spec.start_part]->extra(HA_EXTRA_PREPARE_FOR_UPDATE);
}
break;
case HA_EXTRA_NORMAL:
case HA_EXTRA_QUICK:
case HA_EXTRA_PREPARE_FOR_DROP:
case HA_EXTRA_FLUSH_CACHE:
{
DBUG_RETURN(loop_partitions(extra_cb, &operation));
}
case HA_EXTRA_NO_READCHECK:
{
/*
This is only done as a part of ha_open, which is also used in
ha_partition::open, so no need to do anything.
*/
break;
}
case HA_EXTRA_CACHE:
{
prepare_extra_cache(0);
break;
}
case HA_EXTRA_NO_CACHE:
{
int ret= 0;
if (m_extra_cache_part_id != NO_CURRENT_PART_ID)
ret= m_file[m_extra_cache_part_id]->extra(HA_EXTRA_NO_CACHE);
m_extra_cache= FALSE;
m_extra_cache_size= 0;
m_extra_prepare_for_update= FALSE;
m_extra_cache_part_id= NO_CURRENT_PART_ID;
DBUG_RETURN(ret);
}
case HA_EXTRA_WRITE_CACHE:
{
m_extra_cache= FALSE;
m_extra_cache_size= 0;
m_extra_prepare_for_update= FALSE;
m_extra_cache_part_id= NO_CURRENT_PART_ID;
DBUG_RETURN(loop_partitions(extra_cb, &operation));
}
case HA_EXTRA_IGNORE_NO_KEY:
case HA_EXTRA_NO_IGNORE_NO_KEY:
{
/*
Ignore as these are specific to NDB for handling
idempotency
*/
break;
}
case HA_EXTRA_WRITE_CAN_REPLACE:
case HA_EXTRA_WRITE_CANNOT_REPLACE:
{
/*
Informs handler that write_row() can replace rows which conflict
with row being inserted by PK/unique key without reporting error
to the SQL-layer.
This optimization is not safe for partitioned table in general case
since we may have to put new version of row into partition which is
different from partition in which old version resides (for example
when we partition by non-PK column or by some column which is not
part of unique key which were violated).
And since NDB which is the only engine at the moment that supports
this optimization handles partitioning on its own we simple disable
it here. (BTW for NDB this optimization is safe since it supports
only KEY partitioning and won't use this optimization for tables
which have additional unique constraints).
*/
break;
}
/* Category 7), used by federated handlers */
case HA_EXTRA_INSERT_WITH_UPDATE:
DBUG_RETURN(loop_partitions(extra_cb, &operation));
/* Category 8) Operations only used by NDB */
case HA_EXTRA_DELETE_CANNOT_BATCH:
case HA_EXTRA_UPDATE_CANNOT_BATCH:
{
/* Currently only NDB use the *_CANNOT_BATCH */
break;
}
/* Category 9) Operations only used by MERGE */
case HA_EXTRA_ADD_CHILDREN_LIST:
case HA_EXTRA_ATTACH_CHILDREN:
case HA_EXTRA_IS_ATTACHED_CHILDREN:
case HA_EXTRA_DETACH_CHILDREN:
{
/* Special actions for MERGE tables. Ignore. */
break;
}
/*
http://dev.mysql.com/doc/refman/5.1/en/partitioning-limitations.html
says we no longer support logging to partitioned tables, so we fail
here.
*/
case HA_EXTRA_MARK_AS_LOG_TABLE:
DBUG_RETURN(ER_UNSUPORTED_LOG_ENGINE);
case HA_EXTRA_BEGIN_ALTER_COPY:
case HA_EXTRA_END_ALTER_COPY:
case HA_EXTRA_FAKE_START_STMT:
DBUG_RETURN(loop_partitions(extra_cb, &operation));
default:
{
/* Temporary crash to discover what is wrong */
DBUG_ASSERT(0);
break;
}
}
DBUG_RETURN(0);
}
/**
Special extra call to reset extra parameters
@return Operation status.
@retval >0 Error code
@retval 0 Success
@note Called at end of each statement to reset buffers.
To avoid excessive calls, the m_partitions_to_reset bitmap keep records
of which partitions that have been used in extra(), external_lock() or
start_stmt() and is needed to be called.
*/
int ha_partition::reset(void)
{
int result= 0;
int tmp;
uint i;
DBUG_ENTER("ha_partition::reset");
for (i= bitmap_get_first_set(&m_partitions_to_reset);
i < m_tot_parts;
i= bitmap_get_next_set(&m_partitions_to_reset, i))
{
if ((tmp= m_file[i]->ha_reset()))
result= tmp;
}
bitmap_clear_all(&m_partitions_to_reset);
m_extra_prepare_for_update= FALSE;
DBUG_RETURN(result);
}
/*
Special extra method with additional parameter
See @ref ha_partition::extra
@param[in] operation operation to execute
@param[in] arg extra argument
@return status
@retval 0 success
@retval >0 error code
@detail
Operations supported by extra_opt:
HA_EXTRA_KEYREAD:
arg is interpreted as key index
HA_EXTRA_CACHE:
arg is interpreted as size of cache in full table scan
For detailed description refer to @ref ha_partition::extra
*/
int ha_partition::extra_opt(enum ha_extra_function operation, ulong arg)
{
DBUG_ENTER("ha_partition::extra_opt");
switch (operation)
{
case HA_EXTRA_KEYREAD:
DBUG_RETURN(loop_partitions(start_keyread_cb, &arg));
case HA_EXTRA_CACHE:
prepare_extra_cache(arg);
DBUG_RETURN(0);
default:
DBUG_ASSERT(0);
}
DBUG_RETURN(0);
}
/*
Call extra on handler with HA_EXTRA_CACHE and cachesize
SYNOPSIS
prepare_extra_cache()
cachesize Size of cache for full table scan
RETURN VALUE
NONE
*/
void ha_partition::prepare_extra_cache(uint cachesize)
{
DBUG_ENTER("ha_partition::prepare_extra_cache");
DBUG_PRINT("info", ("cachesize %u", cachesize));
m_extra_cache= TRUE;
m_extra_cache_size= cachesize;
if (m_part_spec.start_part != NO_CURRENT_PART_ID)
{
DBUG_ASSERT(bitmap_is_set(&m_partitions_to_reset,
m_part_spec.start_part));
bitmap_set_bit(&m_partitions_to_reset, m_part_spec.start_part);
late_extra_cache(m_part_spec.start_part);
}
DBUG_VOID_RETURN;
}
/**
Prepares our new and reorged handlers for rename or delete.
@param operation Operation to forward
@return Operation status
@retval 0 Success
@retval !0 Error
*/
int ha_partition::loop_extra_alter(enum ha_extra_function operation)
{
int result= 0, tmp;
handler **file;
DBUG_ENTER("ha_partition::loop_extra_alter");
DBUG_ASSERT(operation == HA_EXTRA_PREPARE_FOR_RENAME ||
operation == HA_EXTRA_FORCE_REOPEN);
if (m_new_file != NULL)
{
for (file= m_new_file; *file; file++)
if ((tmp= (*file)->extra(operation)))
result= tmp;
}
if (m_reorged_file != NULL)
{
for (file= m_reorged_file; *file; file++)
if ((tmp= (*file)->extra(operation)))
result= tmp;
}
if ((tmp= loop_partitions(extra_cb, &operation)))
result= tmp;
DBUG_RETURN(result);
}
/**
Call callback(part, param) on all partitions
@param callback a callback to call for each partition
@param param a void*-parameter passed to callback
@return Operation status
@retval >0 Error code
@retval 0 Success
*/
int ha_partition::loop_partitions(handler_callback callback, void *param)
{
int result= 0, tmp;
uint i;
DBUG_ENTER("ha_partition::loop_partitions");
for (i= bitmap_get_first_set(&m_part_info->lock_partitions);
i < m_tot_parts;
i= bitmap_get_next_set(&m_part_info->lock_partitions, i))
{
if ((tmp= callback(m_file[i], param)))
result= tmp;
}
/* Add all used partitions to be called in reset(). */
bitmap_union(&m_partitions_to_reset, &m_part_info->lock_partitions);
DBUG_RETURN(result);
}
/*
Call extra(HA_EXTRA_CACHE) on next partition_id
SYNOPSIS
late_extra_cache()
partition_id Partition id to call extra on
RETURN VALUE
NONE
*/
void ha_partition::late_extra_cache(uint partition_id)
{
handler *file;
DBUG_ENTER("ha_partition::late_extra_cache");
DBUG_PRINT("info", ("extra_cache %u prepare %u partid %u size %u",
m_extra_cache, m_extra_prepare_for_update,
partition_id, m_extra_cache_size));
if (!m_extra_cache && !m_extra_prepare_for_update)
DBUG_VOID_RETURN;
file= m_file[partition_id];
if (m_extra_cache)
{
if (m_extra_cache_size == 0)
(void) file->extra(HA_EXTRA_CACHE);
else
(void) file->extra_opt(HA_EXTRA_CACHE, m_extra_cache_size);
}
if (m_extra_prepare_for_update)
{
DBUG_ASSERT(m_extra_cache);
(void) file->extra(HA_EXTRA_PREPARE_FOR_UPDATE);
}
m_extra_cache_part_id= partition_id;
DBUG_VOID_RETURN;
}
/*
Call extra(HA_EXTRA_NO_CACHE) on next partition_id
SYNOPSIS
late_extra_no_cache()
partition_id Partition id to call extra on
RETURN VALUE
NONE
*/
void ha_partition::late_extra_no_cache(uint partition_id)
{
handler *file;
DBUG_ENTER("ha_partition::late_extra_no_cache");
if (!m_extra_cache && !m_extra_prepare_for_update)
DBUG_VOID_RETURN;
file= m_file[partition_id];
(void) file->extra(HA_EXTRA_NO_CACHE);
DBUG_ASSERT(partition_id == m_extra_cache_part_id);
m_extra_cache_part_id= NO_CURRENT_PART_ID;
DBUG_VOID_RETURN;
}
/****************************************************************************
MODULE optimiser support
****************************************************************************/
/**
Get keys to use for scanning.
@return key_map of keys usable for scanning
@note No need to use read_partitions here, since it does not depend on
which partitions is used, only which storage engine used.
*/
const key_map *ha_partition::keys_to_use_for_scanning()
{
DBUG_ENTER("ha_partition::keys_to_use_for_scanning");
DBUG_RETURN(m_file[0]->keys_to_use_for_scanning());
}
/**
Minimum number of rows to base optimizer estimate on.
*/
ha_rows ha_partition::min_rows_for_estimate()
{
uint i, max_used_partitions, tot_used_partitions;
DBUG_ENTER("ha_partition::min_rows_for_estimate");
tot_used_partitions= bitmap_bits_set(&m_part_info->read_partitions);
/*
All partitions might have been left as unused during partition pruning
due to, for example, an impossible WHERE condition. Nonetheless, the
optimizer might still attempt to perform (e.g. range) analysis where an
estimate of the the number of rows is calculated using records_in_range.
Hence, to handle this and other possible cases, use zero as the minimum
number of rows to base the estimate on if no partition is being used.
*/
if (!tot_used_partitions)
DBUG_RETURN(0);
/*
Allow O(log2(tot_partitions)) increase in number of used partitions.
This gives O(tot_rows/log2(tot_partitions)) rows to base the estimate on.
I.e when the total number of partitions doubles, allow one more
partition to be checked.
*/
i= 2;
max_used_partitions= 1;
while (i < m_tot_parts)
{
max_used_partitions++;
i= i << 1;
}
if (max_used_partitions > tot_used_partitions)
max_used_partitions= tot_used_partitions;
/* stats.records is already updated by the info(HA_STATUS_VARIABLE) call. */
DBUG_PRINT("info", ("max_used_partitions: %u tot_rows: %lu",
max_used_partitions,
(ulong) stats.records));
DBUG_PRINT("info", ("tot_used_partitions: %u min_rows_to_check: %lu",
tot_used_partitions,
(ulong) stats.records * max_used_partitions
/ tot_used_partitions));
DBUG_RETURN(stats.records * max_used_partitions / tot_used_partitions);
}
/**
Get the biggest used partition.
Starting at the N:th biggest partition and skips all non used
partitions, returning the biggest used partition found
@param[in,out] part_index Skip the *part_index biggest partitions
@return The biggest used partition with index not lower than *part_index.
@retval NO_CURRENT_PART_ID No more partition used.
@retval != NO_CURRENT_PART_ID partition id of biggest used partition with
index >= *part_index supplied. Note that
*part_index will be updated to the next
partition index to use.
*/
uint ha_partition::get_biggest_used_partition(uint *part_index)
{
uint part_id;
while ((*part_index) < m_tot_parts)
{
part_id= m_part_ids_sorted_by_num_of_records[(*part_index)++];
if (bitmap_is_set(&m_part_info->read_partitions, part_id))
return part_id;
}
return NO_CURRENT_PART_ID;
}
/*
Return time for a scan of the table
SYNOPSIS
scan_time()
RETURN VALUE
time for scan
*/
double ha_partition::scan_time()
{
double scan_time= 0;
uint i;
DBUG_ENTER("ha_partition::scan_time");
for (i= bitmap_get_first_set(&m_part_info->read_partitions);
i < m_tot_parts;
i= bitmap_get_next_set(&m_part_info->read_partitions, i))
scan_time+= m_file[i]->scan_time();
DBUG_RETURN(scan_time);
}
/**
Find number of records in a range.
@param inx Index number
@param min_key Start of range
@param max_key End of range
@return Number of rows in range.
Given a starting key, and an ending key estimate the number of rows that
will exist between the two. max_key may be empty which in case determine
if start_key matches any rows.
*/
ha_rows ha_partition::records_in_range(uint inx, key_range *min_key,
key_range *max_key)
{
ha_rows min_rows_to_check, rows, estimated_rows=0, checked_rows= 0;
uint partition_index= 0, part_id;
DBUG_ENTER("ha_partition::records_in_range");
min_rows_to_check= min_rows_for_estimate();
while ((part_id= get_biggest_used_partition(&partition_index))
!= NO_CURRENT_PART_ID)
{
rows= m_file[part_id]->records_in_range(inx, min_key, max_key);
DBUG_PRINT("info", ("part %u match %lu rows of %lu", part_id, (ulong) rows,
(ulong) m_file[part_id]->stats.records));
if (rows == HA_POS_ERROR)
DBUG_RETURN(HA_POS_ERROR);
estimated_rows+= rows;
checked_rows+= m_file[part_id]->stats.records;
/*
Returning 0 means no rows can be found, so we must continue
this loop as long as we have estimated_rows == 0.
Also many engines return 1 to indicate that there may exist
a matching row, we do not normalize this by dividing by number of
used partitions, but leave it to be returned as a sum, which will
reflect that we will need to scan each partition's index.
Note that this statistics may not always be correct, so we must
continue even if the current partition has 0 rows, since we might have
deleted rows from the current partition, or inserted to the next
partition.
*/
if (estimated_rows && checked_rows &&
checked_rows >= min_rows_to_check)
{
DBUG_PRINT("info",
("records_in_range(inx %u): %lu (%lu * %lu / %lu)",
inx,
(ulong) (estimated_rows * stats.records / checked_rows),
(ulong) estimated_rows,
(ulong) stats.records,
(ulong) checked_rows));
DBUG_RETURN(estimated_rows * stats.records / checked_rows);
}
}
DBUG_PRINT("info", ("records_in_range(inx %u): %lu",
inx,
(ulong) estimated_rows));
DBUG_RETURN(estimated_rows);
}
/**
Estimate upper bound of number of rows.
@return Number of rows.
*/
ha_rows ha_partition::estimate_rows_upper_bound()
{
ha_rows rows, tot_rows= 0;
handler **file= m_file;
DBUG_ENTER("ha_partition::estimate_rows_upper_bound");
do
{
if (bitmap_is_set(&(m_part_info->read_partitions), (uint)(file - m_file)))
{
rows= (*file)->estimate_rows_upper_bound();
if (rows == HA_POS_ERROR)
DBUG_RETURN(HA_POS_ERROR);
tot_rows+= rows;
}
} while (*(++file));
DBUG_RETURN(tot_rows);
}
/*
Get time to read
SYNOPSIS
read_time()
index Index number used
ranges Number of ranges
rows Number of rows
RETURN VALUE
time for read
DESCRIPTION
This will be optimised later to include whether or not the index can
be used with partitioning. To achieve we need to add another parameter
that specifies how many of the index fields that are bound in the ranges.
Possibly added as a new call to handlers.
*/
double ha_partition::read_time(uint index, uint ranges, ha_rows rows)
{
DBUG_ENTER("ha_partition::read_time");
DBUG_RETURN(m_file[0]->read_time(index, ranges, rows));
}
/**
Number of rows in table. see handler.h
@return Number of records in the table (after pruning!)
*/
ha_rows ha_partition::records()
{
ha_rows rows, tot_rows= 0;
uint i;
DBUG_ENTER("ha_partition::records");
for (i= bitmap_get_first_set(&m_part_info->read_partitions);
i < m_tot_parts;
i= bitmap_get_next_set(&m_part_info->read_partitions, i))
{
rows= m_file[i]->records();
if (rows == HA_POS_ERROR)
DBUG_RETURN(HA_POS_ERROR);
tot_rows+= rows;
}
DBUG_RETURN(tot_rows);
}
/*
Is it ok to switch to a new engine for this table
SYNOPSIS
can_switch_engine()
RETURN VALUE
TRUE Ok
FALSE Not ok
DESCRIPTION
Used to ensure that tables with foreign key constraints are not moved
to engines without foreign key support.
*/
bool ha_partition::can_switch_engines()
{
handler **file;
DBUG_ENTER("ha_partition::can_switch_engines");
file= m_file;
do
{
if (!(*file)->can_switch_engines())
DBUG_RETURN(FALSE);
} while (*(++file));
DBUG_RETURN(TRUE);
}
/*
Is table cache supported
SYNOPSIS
table_cache_type()
*/
uint8 ha_partition::table_cache_type()
{
DBUG_ENTER("ha_partition::table_cache_type");
DBUG_RETURN(m_file[0]->table_cache_type());
}
/**
Calculate hash value for KEY partitioning using an array of fields.
@param field_array An array of the fields in KEY partitioning
@return hash_value calculated
@note Uses the hash function on the character set of the field.
Integer and floating point fields use the binary character set by default.
*/
uint32 ha_partition::calculate_key_hash_value(Field **field_array)
{
ulong nr1= 1;
ulong nr2= 4;
bool use_51_hash;
use_51_hash= MY_TEST((*field_array)->table->part_info->key_algorithm ==
partition_info::KEY_ALGORITHM_51);
do
{
Field *field= *field_array;
if (use_51_hash)
{
switch (field->real_type()) {
case MYSQL_TYPE_TINY:
case MYSQL_TYPE_SHORT:
case MYSQL_TYPE_LONG:
case MYSQL_TYPE_FLOAT:
case MYSQL_TYPE_DOUBLE:
case MYSQL_TYPE_NEWDECIMAL:
case MYSQL_TYPE_TIMESTAMP:
case MYSQL_TYPE_LONGLONG:
case MYSQL_TYPE_INT24:
case MYSQL_TYPE_TIME:
case MYSQL_TYPE_DATETIME:
case MYSQL_TYPE_YEAR:
case MYSQL_TYPE_NEWDATE:
{
if (field->is_null())
{
nr1^= (nr1 << 1) | 1;
continue;
}
/* Force this to my_hash_sort_bin, which was used in 5.1! */
uint len= field->pack_length();
my_charset_bin.coll->hash_sort(&my_charset_bin, field->ptr, len,
&nr1, &nr2);
/* Done with this field, continue with next one. */
continue;
}
case MYSQL_TYPE_STRING:
case MYSQL_TYPE_VARCHAR:
case MYSQL_TYPE_BIT:
/* Not affected, same in 5.1 and 5.5 */
break;
/*
ENUM/SET uses my_hash_sort_simple in 5.1 (i.e. my_charset_latin1)
and my_hash_sort_bin in 5.5!
*/
case MYSQL_TYPE_ENUM:
case MYSQL_TYPE_SET:
{
if (field->is_null())
{
nr1^= (nr1 << 1) | 1;
continue;
}
/* Force this to my_hash_sort_bin, which was used in 5.1! */
uint len= field->pack_length();
my_charset_latin1.coll->hash_sort(&my_charset_latin1, field->ptr,
len, &nr1, &nr2);
continue;
}
/* New types in mysql-5.6. */
case MYSQL_TYPE_DATETIME2:
case MYSQL_TYPE_TIME2:
case MYSQL_TYPE_TIMESTAMP2:
/* Not affected, 5.6+ only! */
break;
/* These types should not be allowed for partitioning! */
case MYSQL_TYPE_NULL:
case MYSQL_TYPE_DECIMAL:
case MYSQL_TYPE_DATE:
case MYSQL_TYPE_TINY_BLOB:
case MYSQL_TYPE_MEDIUM_BLOB:
case MYSQL_TYPE_LONG_BLOB:
case MYSQL_TYPE_BLOB:
case MYSQL_TYPE_VAR_STRING:
case MYSQL_TYPE_GEOMETRY:
/* fall through */
default:
DBUG_ASSERT(0); // New type?
/* Fall through for default hashing (5.5). */
}
/* fall through, use collation based hashing. */
}
field->hash(&nr1, &nr2);
} while (*(++field_array));
return (uint32) nr1;
}
/****************************************************************************
MODULE print messages
****************************************************************************/
const char *ha_partition::index_type(uint inx)
{
uint first_used_partition;
DBUG_ENTER("ha_partition::index_type");
first_used_partition= bitmap_get_first_set(&(m_part_info->read_partitions));
if (first_used_partition == MY_BIT_NONE)
{
DBUG_ASSERT(0); // How can this happen?
DBUG_RETURN(handler::index_type(inx));
}
DBUG_RETURN(m_file[first_used_partition]->index_type(inx));
}
enum row_type ha_partition::get_row_type() const
{
uint i;
enum row_type type;
DBUG_ENTER("ha_partition::get_row_type");
i= bitmap_get_first_set(&m_part_info->read_partitions);
DBUG_ASSERT(i < m_tot_parts);
if (i >= m_tot_parts)
DBUG_RETURN(ROW_TYPE_NOT_USED);
type= m_file[i]->get_row_type();
DBUG_PRINT("info", ("partition %u, row_type: %d", i, type));
for (i= bitmap_get_next_set(&m_part_info->lock_partitions, i);
i < m_tot_parts;
i= bitmap_get_next_set(&m_part_info->lock_partitions, i))
{
enum row_type part_type= m_file[i]->get_row_type();
DBUG_PRINT("info", ("partition %u, row_type: %d", i, type));
if (part_type != type)
DBUG_RETURN(ROW_TYPE_NOT_USED);
}
DBUG_RETURN(type);
}
void ha_partition::append_row_to_str(String &str)
{
const uchar *rec;
bool is_rec0= !m_err_rec || m_err_rec == table->record[0];
if (is_rec0)
rec= table->record[0];
else
rec= m_err_rec;
// If PK, use full PK instead of full part field array!
if (table->s->primary_key != MAX_KEY)
{
KEY *key= table->key_info + table->s->primary_key;
KEY_PART_INFO *key_part= key->key_part;
KEY_PART_INFO *key_part_end= key_part + key->user_defined_key_parts;
if (!is_rec0)
set_key_field_ptr(key, rec, table->record[0]);
for (; key_part != key_part_end; key_part++)
{
Field *field= key_part->field;
str.append(" ");
str.append(field->field_name);
str.append(":");
field_unpack(&str, field, rec, 0, false);
}
if (!is_rec0)
set_key_field_ptr(key, table->record[0], rec);
}
else
{
Field **field_ptr;
if (!is_rec0)
table->move_fields(m_part_info->full_part_field_array, rec,
table->record[0]);
/* No primary key, use full partition field array. */
for (field_ptr= m_part_info->full_part_field_array;
*field_ptr;
field_ptr++)
{
Field *field= *field_ptr;
str.append(" ");
str.append(field->field_name);
str.append(":");
field_unpack(&str, field, rec, 0, false);
}
if (!is_rec0)
table->move_fields(m_part_info->full_part_field_array, table->record[0],
rec);
}
}
void ha_partition::print_error(int error, myf errflag)
{
THD *thd= ha_thd();
DBUG_ENTER("ha_partition::print_error");
/* Should probably look for my own errors first */
DBUG_PRINT("enter", ("error: %d", error));
if ((error == HA_ERR_NO_PARTITION_FOUND) &&
! (thd->lex->alter_info.flags & Alter_info::ALTER_TRUNCATE_PARTITION))
{
m_part_info->print_no_partition_found(table, errflag);
DBUG_VOID_RETURN;
}
else if (error == HA_ERR_ROW_IN_WRONG_PARTITION)
{
/* Should only happen on DELETE or UPDATE! */
DBUG_ASSERT(thd_sql_command(thd) == SQLCOM_DELETE ||
thd_sql_command(thd) == SQLCOM_DELETE_MULTI ||
thd_sql_command(thd) == SQLCOM_UPDATE ||
thd_sql_command(thd) == SQLCOM_UPDATE_MULTI);
DBUG_ASSERT(m_err_rec);
if (m_err_rec)
{
uint max_length;
char buf[MAX_KEY_LENGTH];
String str(buf,sizeof(buf),system_charset_info);
uint32 part_id;
str.length(0);
str.append("(");
str.append_ulonglong(m_last_part);
str.append(" != ");
if (get_part_for_delete(m_err_rec, m_rec0, m_part_info, &part_id))
str.append("?");
else
str.append_ulonglong(part_id);
str.append(")");
append_row_to_str(str);
/* Log this error, so the DBA can notice it and fix it! */
sql_print_error("Table '%-192s' corrupted: row in wrong partition: %s\n"
"Please REPAIR the table!",
table->s->table_name.str,
str.c_ptr_safe());
max_length= (MYSQL_ERRMSG_SIZE -
(uint) strlen(ER_THD(thd, ER_ROW_IN_WRONG_PARTITION)));
if (str.length() >= max_length)
{
str.length(max_length-4);
str.append(STRING_WITH_LEN("..."));
}
my_error(ER_ROW_IN_WRONG_PARTITION, MYF(0), str.c_ptr_safe());
m_err_rec= NULL;
DBUG_VOID_RETURN;
}
/* fall through to generic error handling. */
}
/* In case m_file has not been initialized, like in bug#42438 */
if (m_file)
{
if (m_last_part >= m_tot_parts)
{
DBUG_ASSERT(0);
m_last_part= 0;
}
m_file[m_last_part]->print_error(error, errflag);
}
else
handler::print_error(error, errflag);
DBUG_VOID_RETURN;
}
bool ha_partition::get_error_message(int error, String *buf)
{
DBUG_ENTER("ha_partition::get_error_message");
/* Should probably look for my own errors first */
/* In case m_file has not been initialized, like in bug#42438 */
if (m_file)
DBUG_RETURN(m_file[m_last_part]->get_error_message(error, buf));
DBUG_RETURN(handler::get_error_message(error, buf));
}
/****************************************************************************
MODULE in-place ALTER
****************************************************************************/
/**
Get table flags.
*/
handler::Table_flags ha_partition::table_flags() const
{
uint first_used_partition= 0;
DBUG_ENTER("ha_partition::table_flags");
if (m_handler_status < handler_initialized ||
m_handler_status >= handler_closed)
DBUG_RETURN(PARTITION_ENABLED_TABLE_FLAGS);
if (get_lock_type() != F_UNLCK)
{
/*
The flags are cached after external_lock, and may depend on isolation
level. So we should use a locked partition to get the correct flags.
*/
first_used_partition= bitmap_get_first_set(&m_part_info->lock_partitions);
if (first_used_partition == MY_BIT_NONE)
first_used_partition= 0;
}
DBUG_RETURN((m_file[first_used_partition]->ha_table_flags() &
~(PARTITION_DISABLED_TABLE_FLAGS)) |
(PARTITION_ENABLED_TABLE_FLAGS));
}
/**
alter_table_flags must be on handler/table level, not on hton level
due to the ha_partition hton does not know what the underlying hton is.
*/
uint ha_partition::alter_table_flags(uint flags)
{
uint flags_to_return;
DBUG_ENTER("ha_partition::alter_table_flags");
flags_to_return= ht->alter_table_flags(flags);
flags_to_return|= m_file[0]->alter_table_flags(flags);
DBUG_RETURN(flags_to_return);
}
/**
check if copy of data is needed in alter table.
*/
bool ha_partition::check_if_incompatible_data(HA_CREATE_INFO *create_info,
uint table_changes)
{
/*
The check for any partitioning related changes have already been done
in mysql_alter_table (by fix_partition_func), so it is only up to
the underlying handlers.
*/
List_iterator<partition_element> part_it(m_part_info->partitions);
HA_CREATE_INFO dummy_info= *create_info;
uint i=0;
while (partition_element *part_elem= part_it++)
{
if (m_is_sub_partitioned)
{
List_iterator<partition_element> subpart_it(part_elem->subpartitions);
while (partition_element *sub_elem= subpart_it++)
{
dummy_info.data_file_name= sub_elem->data_file_name;
dummy_info.index_file_name= sub_elem->index_file_name;
if (m_file[i++]->check_if_incompatible_data(&dummy_info, table_changes))
return COMPATIBLE_DATA_NO;
}
}
else
{
dummy_info.data_file_name= part_elem->data_file_name;
dummy_info.index_file_name= part_elem->index_file_name;
if (m_file[i++]->check_if_incompatible_data(&dummy_info, table_changes))
return COMPATIBLE_DATA_NO;
}
}
return COMPATIBLE_DATA_YES;
}
/**
Support of in-place alter table.
*/
/**
Helper class for in-place alter, see handler.h
*/
class ha_partition_inplace_ctx : public inplace_alter_handler_ctx
{
public:
inplace_alter_handler_ctx **handler_ctx_array;
private:
uint m_tot_parts;
public:
ha_partition_inplace_ctx(THD *thd, uint tot_parts)
: inplace_alter_handler_ctx(),
handler_ctx_array(NULL),
m_tot_parts(tot_parts)
{}
~ha_partition_inplace_ctx()
{
if (handler_ctx_array)
{
for (uint index= 0; index < m_tot_parts; index++)
delete handler_ctx_array[index];
}
}
};
enum_alter_inplace_result
ha_partition::check_if_supported_inplace_alter(TABLE *altered_table,
Alter_inplace_info *ha_alter_info)
{
uint index= 0;
enum_alter_inplace_result result= HA_ALTER_INPLACE_NO_LOCK;
ha_partition_inplace_ctx *part_inplace_ctx;
bool first_is_set= false;
THD *thd= ha_thd();
DBUG_ENTER("ha_partition::check_if_supported_inplace_alter");
/*
Support inplace change of KEY () -> KEY ALGORITHM = N ().
Any other change would set partition_changed in
prep_alter_part_table() in mysql_alter_table().
*/
if (ha_alter_info->alter_info->flags == Alter_info::ALTER_PARTITION)
DBUG_RETURN(HA_ALTER_INPLACE_NO_LOCK);
part_inplace_ctx=
new (thd->mem_root) ha_partition_inplace_ctx(thd, m_tot_parts);
if (!part_inplace_ctx)
DBUG_RETURN(HA_ALTER_ERROR);
part_inplace_ctx->handler_ctx_array= (inplace_alter_handler_ctx **)
thd->alloc(sizeof(inplace_alter_handler_ctx *) * (m_tot_parts + 1));
if (!part_inplace_ctx->handler_ctx_array)
DBUG_RETURN(HA_ALTER_ERROR);
/* Set all to NULL, including the terminating one. */
for (index= 0; index <= m_tot_parts; index++)
part_inplace_ctx->handler_ctx_array[index]= NULL;
ha_alter_info->handler_flags |= Alter_inplace_info::ALTER_PARTITIONED;
for (index= 0; index < m_tot_parts; index++)
{
enum_alter_inplace_result p_result=
m_file[index]->check_if_supported_inplace_alter(altered_table,
ha_alter_info);
part_inplace_ctx->handler_ctx_array[index]= ha_alter_info->handler_ctx;
if (index == 0)
{
first_is_set= (ha_alter_info->handler_ctx != NULL);
}
else if (first_is_set != (ha_alter_info->handler_ctx != NULL))
{
/* Either none or all partitions must set handler_ctx! */
DBUG_ASSERT(0);
DBUG_RETURN(HA_ALTER_ERROR);
}
if (p_result < result)
result= p_result;
if (result == HA_ALTER_ERROR)
break;
}
ha_alter_info->handler_ctx= part_inplace_ctx;
/*
To indicate for future inplace calls that there are several
partitions/handlers that need to be committed together,
we set group_commit_ctx to the NULL terminated array of
the partitions handlers.
*/
ha_alter_info->group_commit_ctx= part_inplace_ctx->handler_ctx_array;
DBUG_RETURN(result);
}
bool ha_partition::prepare_inplace_alter_table(TABLE *altered_table,
Alter_inplace_info *ha_alter_info)
{
uint index= 0;
bool error= false;
ha_partition_inplace_ctx *part_inplace_ctx;
DBUG_ENTER("ha_partition::prepare_inplace_alter_table");
/*
Changing to similar partitioning, only update metadata.
Non allowed changes would be caught in prep_alter_part_table().
*/
if (ha_alter_info->alter_info->flags == Alter_info::ALTER_PARTITION)
DBUG_RETURN(false);
part_inplace_ctx=
static_cast<class ha_partition_inplace_ctx*>(ha_alter_info->handler_ctx);
for (index= 0; index < m_tot_parts && !error; index++)
{
ha_alter_info->handler_ctx= part_inplace_ctx->handler_ctx_array[index];
if (m_file[index]->ha_prepare_inplace_alter_table(altered_table,
ha_alter_info))
error= true;
part_inplace_ctx->handler_ctx_array[index]= ha_alter_info->handler_ctx;
}
ha_alter_info->handler_ctx= part_inplace_ctx;
DBUG_RETURN(error);
}
bool ha_partition::inplace_alter_table(TABLE *altered_table,
Alter_inplace_info *ha_alter_info)
{
uint index= 0;
bool error= false;
ha_partition_inplace_ctx *part_inplace_ctx;
DBUG_ENTER("ha_partition::inplace_alter_table");
/*
Changing to similar partitioning, only update metadata.
Non allowed changes would be caught in prep_alter_part_table().
*/
if (ha_alter_info->alter_info->flags == Alter_info::ALTER_PARTITION)
DBUG_RETURN(false);
part_inplace_ctx=
static_cast<class ha_partition_inplace_ctx*>(ha_alter_info->handler_ctx);
for (index= 0; index < m_tot_parts && !error; index++)
{
if ((ha_alter_info->handler_ctx=
part_inplace_ctx->handler_ctx_array[index]) != NULL
&& index != 0)
ha_alter_info->handler_ctx->set_shared_data
(*part_inplace_ctx->handler_ctx_array[index - 1]);
if (m_file[index]->ha_inplace_alter_table(altered_table,
ha_alter_info))
error= true;
part_inplace_ctx->handler_ctx_array[index]= ha_alter_info->handler_ctx;
}
ha_alter_info->handler_ctx= part_inplace_ctx;
DBUG_RETURN(error);
}
/*
Note that this function will try rollback failed ADD INDEX by
executing DROP INDEX for the indexes that were committed (if any)
before the error occurred. This means that the underlying storage
engine must be able to drop index in-place with X-lock held.
(As X-lock will be held here if new indexes are to be committed)
*/
bool ha_partition::commit_inplace_alter_table(TABLE *altered_table,
Alter_inplace_info *ha_alter_info,
bool commit)
{
ha_partition_inplace_ctx *part_inplace_ctx;
bool error= false;
DBUG_ENTER("ha_partition::commit_inplace_alter_table");
/*
Changing to similar partitioning, only update metadata.
Non allowed changes would be caught in prep_alter_part_table().
*/
if (ha_alter_info->alter_info->flags == Alter_info::ALTER_PARTITION)
DBUG_RETURN(false);
part_inplace_ctx=
static_cast<class ha_partition_inplace_ctx*>(ha_alter_info->handler_ctx);
if (commit)
{
DBUG_ASSERT(ha_alter_info->group_commit_ctx ==
part_inplace_ctx->handler_ctx_array);
ha_alter_info->handler_ctx= part_inplace_ctx->handler_ctx_array[0];
error= m_file[0]->ha_commit_inplace_alter_table(altered_table,
ha_alter_info, commit);
if (error)
goto end;
if (ha_alter_info->group_commit_ctx)
{
/*
If ha_alter_info->group_commit_ctx is not set to NULL,
then the engine did only commit the first partition!
The engine is probably new, since both innodb and the default
implementation of handler::commit_inplace_alter_table sets it to NULL
and simply return false, since it allows metadata changes only.
Loop over all other partitions as to follow the protocol!
*/
uint i;
DBUG_ASSERT(0);
for (i= 1; i < m_tot_parts; i++)
{
ha_alter_info->handler_ctx= part_inplace_ctx->handler_ctx_array[i];
error|= m_file[i]->ha_commit_inplace_alter_table(altered_table,
ha_alter_info,
true);
}
}
}
else
{
uint i;
for (i= 0; i < m_tot_parts; i++)
{
/* Rollback, commit == false, is done for each partition! */
ha_alter_info->handler_ctx= part_inplace_ctx->handler_ctx_array[i];
if (m_file[i]->ha_commit_inplace_alter_table(altered_table,
ha_alter_info, false))
error= true;
}
}
end:
ha_alter_info->handler_ctx= part_inplace_ctx;
DBUG_RETURN(error);
}
void ha_partition::notify_table_changed()
{
handler **file;
DBUG_ENTER("ha_partition::notify_table_changed");
for (file= m_file; *file; file++)
(*file)->ha_notify_table_changed();
DBUG_VOID_RETURN;
}
uint ha_partition::min_of_the_max_uint(
uint (handler::*operator_func)(void) const) const
{
handler **file;
uint min_of_the_max= ((*m_file)->*operator_func)();
for (file= m_file+1; *file; file++)
{
uint tmp= ((*file)->*operator_func)();
set_if_smaller(min_of_the_max, tmp);
}
return min_of_the_max;
}
uint ha_partition::max_supported_key_parts() const
{
return min_of_the_max_uint(&handler::max_supported_key_parts);
}
uint ha_partition::max_supported_key_length() const
{
return min_of_the_max_uint(&handler::max_supported_key_length);
}
uint ha_partition::max_supported_key_part_length() const
{
return min_of_the_max_uint(&handler::max_supported_key_part_length);
}
uint ha_partition::max_supported_record_length() const
{
return min_of_the_max_uint(&handler::max_supported_record_length);
}
uint ha_partition::max_supported_keys() const
{
return min_of_the_max_uint(&handler::max_supported_keys);
}
uint ha_partition::min_record_length(uint options) const
{
handler **file;
uint max= (*m_file)->min_record_length(options);
for (file= m_file, file++; *file; file++)
if (max < (*file)->min_record_length(options))
max= (*file)->min_record_length(options);
return max;
}
/****************************************************************************
MODULE compare records
****************************************************************************/
/*
Compare two positions
SYNOPSIS
cmp_ref()
ref1 First position
ref2 Second position
RETURN VALUE
<0 ref1 < ref2
0 Equal
>0 ref1 > ref2
DESCRIPTION
We get two references and need to check if those records are the same.
If they belong to different partitions we decide that they are not
the same record. Otherwise we use the particular handler to decide if
they are the same. Sort in partition id order if not equal.
MariaDB note:
Please don't merge the code from MySQL that does this:
We get two references and need to check if those records are the same.
If they belong to different partitions we decide that they are not
the same record. Otherwise we use the particular handler to decide if
they are the same. Sort in partition id order if not equal.
It is incorrect, MariaDB has an alternative fix.
*/
int ha_partition::cmp_ref(const uchar *ref1, const uchar *ref2)
{
int cmp;
my_ptrdiff_t diff1, diff2;
DBUG_ENTER("ha_partition::cmp_ref");
cmp = m_file[0]->cmp_ref((ref1 + PARTITION_BYTES_IN_POS),
(ref2 + PARTITION_BYTES_IN_POS));
if (cmp)
DBUG_RETURN(cmp);
if ((ref1[0] == ref2[0]) && (ref1[1] == ref2[1]))
{
/* This means that the references are same and are in same partition.*/
DBUG_RETURN(0);
}
/*
In Innodb we compare with either primary key value or global DB_ROW_ID so
it is not possible that the two references are equal and are in different
partitions, but in myisam it is possible since we are comparing offsets.
Remove this assert if DB_ROW_ID is changed to be per partition.
*/
DBUG_ASSERT(!m_innodb);
diff1= ref2[1] - ref1[1];
diff2= ref2[0] - ref1[0];
if (diff1 > 0)
{
DBUG_RETURN(-1);
}
if (diff1 < 0)
{
DBUG_RETURN(+1);
}
if (diff2 > 0)
{
DBUG_RETURN(-1);
}
DBUG_RETURN(+1);
}
/****************************************************************************
MODULE auto increment
****************************************************************************/
int ha_partition::reset_auto_increment(ulonglong value)
{
handler **file= m_file;
int res;
DBUG_ENTER("ha_partition::reset_auto_increment");
lock_auto_increment();
part_share->auto_inc_initialized= false;
part_share->next_auto_inc_val= 0;
do
{
if ((res= (*file)->ha_reset_auto_increment(value)) != 0)
break;
} while (*(++file));
unlock_auto_increment();
DBUG_RETURN(res);
}
/**
This method is called by update_auto_increment which in turn is called
by the individual handlers as part of write_row. We use the
part_share->next_auto_inc_val, or search all
partitions for the highest auto_increment_value if not initialized or
if auto_increment field is a secondary part of a key, we must search
every partition when holding a mutex to be sure of correctness.
*/
void ha_partition::get_auto_increment(ulonglong offset, ulonglong increment,
ulonglong nb_desired_values,
ulonglong *first_value,
ulonglong *nb_reserved_values)
{
DBUG_ENTER("ha_partition::get_auto_increment");
DBUG_PRINT("info", ("offset: %lu inc: %lu desired_values: %lu "
"first_value: %lu", (ulong) offset, (ulong) increment,
(ulong) nb_desired_values, (ulong) *first_value));
DBUG_ASSERT(increment);
DBUG_ASSERT(nb_desired_values);
*first_value= 0;
if (table->s->next_number_keypart)
{
/*
next_number_keypart is != 0 if the auto_increment column is a secondary
column in the index (it is allowed in MyISAM)
*/
DBUG_PRINT("info", ("next_number_keypart != 0"));
ulonglong nb_reserved_values_part;
ulonglong first_value_part, max_first_value;
handler **file= m_file;
first_value_part= max_first_value= *first_value;
/* Must find highest value among all partitions. */
do
{
/* Only nb_desired_values = 1 makes sense */
(*file)->get_auto_increment(offset, increment, 1,
&first_value_part, &nb_reserved_values_part);
if (first_value_part == ULONGLONG_MAX) // error in one partition
{
*first_value= first_value_part;
/* log that the error was between table/partition handler */
sql_print_error("Partition failed to reserve auto_increment value");
DBUG_VOID_RETURN;
}
DBUG_PRINT("info", ("first_value_part: %lu", (ulong) first_value_part));
set_if_bigger(max_first_value, first_value_part);
} while (*(++file));
*first_value= max_first_value;
*nb_reserved_values= 1;
}
else
{
THD *thd= ha_thd();
/*
This is initialized in the beginning of the first write_row call.
*/
DBUG_ASSERT(part_share->auto_inc_initialized);
/*
Get a lock for handling the auto_increment in part_share
for avoiding two concurrent statements getting the same number.
*/
lock_auto_increment();
/*
In a multi-row insert statement like INSERT SELECT and LOAD DATA
where the number of candidate rows to insert is not known in advance
we must hold a lock/mutex for the whole statement if we have statement
based replication. Because the statement-based binary log contains
only the first generated value used by the statement, and slaves assumes
all other generated values used by this statement were consecutive to
this first one, we must exclusively lock the generator until the statement
is done.
*/
if (!auto_increment_safe_stmt_log_lock &&
thd->lex->sql_command != SQLCOM_INSERT &&
mysql_bin_log.is_open() &&
!thd->is_current_stmt_binlog_format_row() &&
(thd->variables.option_bits & OPTION_BIN_LOG))
{
DBUG_PRINT("info", ("locking auto_increment_safe_stmt_log_lock"));
auto_increment_safe_stmt_log_lock= TRUE;
}
/* this gets corrected (for offset/increment) in update_auto_increment */
*first_value= part_share->next_auto_inc_val;
part_share->next_auto_inc_val+= nb_desired_values * increment;
unlock_auto_increment();
DBUG_PRINT("info", ("*first_value: %lu", (ulong) *first_value));
*nb_reserved_values= nb_desired_values;
}
DBUG_VOID_RETURN;
}
void ha_partition::release_auto_increment()
{
DBUG_ENTER("ha_partition::release_auto_increment");
if (table->s->next_number_keypart)
{
uint i;
for (i= bitmap_get_first_set(&m_part_info->lock_partitions);
i < m_tot_parts;
i= bitmap_get_next_set(&m_part_info->lock_partitions, i))
{
m_file[i]->ha_release_auto_increment();
}
}
else
{
lock_auto_increment();
if (next_insert_id)
{
ulonglong next_auto_inc_val= part_share->next_auto_inc_val;
/*
If the current auto_increment values is lower than the reserved
value, and the reserved value was reserved by this thread,
we can lower the reserved value.
*/
if (next_insert_id < next_auto_inc_val &&
auto_inc_interval_for_cur_row.maximum() >= next_auto_inc_val)
{
THD *thd= ha_thd();
/*
Check that we do not lower the value because of a failed insert
with SET INSERT_ID, i.e. forced/non generated values.
*/
if (thd->auto_inc_intervals_forced.maximum() < next_insert_id)
part_share->next_auto_inc_val= next_insert_id;
}
DBUG_PRINT("info", ("part_share->next_auto_inc_val: %lu",
(ulong) part_share->next_auto_inc_val));
}
/*
Unlock the multi-row statement lock taken in get_auto_increment.
These actions must be performed even if the next_insert_id field
contains zero, otherwise if the update_auto_increment fails then
an unnecessary lock will remain:
*/
if (auto_increment_safe_stmt_log_lock)
{
auto_increment_safe_stmt_log_lock= FALSE;
DBUG_PRINT("info", ("unlocking auto_increment_safe_stmt_log_lock"));
}
unlock_auto_increment();
}
DBUG_VOID_RETURN;
}
/****************************************************************************
MODULE initialize handler for HANDLER call
****************************************************************************/
void ha_partition::init_table_handle_for_HANDLER()
{
return;
}
/**
Return the checksum of the table (all partitions)
*/
uint ha_partition::checksum() const
{
ha_checksum sum= 0;
DBUG_ENTER("ha_partition::checksum");
if ((table_flags() & (HA_HAS_OLD_CHECKSUM | HA_HAS_NEW_CHECKSUM)))
{
handler **file= m_file;
do
{
sum+= (*file)->checksum();
} while (*(++file));
}
DBUG_RETURN(sum);
}
/****************************************************************************
MODULE enable/disable indexes
****************************************************************************/
/*
Disable indexes for a while
SYNOPSIS
disable_indexes()
mode Mode
RETURN VALUES
0 Success
!= 0 Error
*/
int ha_partition::disable_indexes(uint mode)
{
handler **file;
int error= 0;
DBUG_ASSERT(bitmap_is_set_all(&(m_part_info->lock_partitions)));
for (file= m_file; *file; file++)
{
if ((error= (*file)->ha_disable_indexes(mode)))
break;
}
return error;
}
/*
Enable indexes again
SYNOPSIS
enable_indexes()
mode Mode
RETURN VALUES
0 Success
!= 0 Error
*/
int ha_partition::enable_indexes(uint mode)
{
handler **file;
int error= 0;
DBUG_ASSERT(bitmap_is_set_all(&(m_part_info->lock_partitions)));
for (file= m_file; *file; file++)
{
if ((error= (*file)->ha_enable_indexes(mode)))
break;
}
return error;
}
/*
Check if indexes are disabled
SYNOPSIS
indexes_are_disabled()
RETURN VALUES
0 Indexes are enabled
!= 0 Indexes are disabled
*/
int ha_partition::indexes_are_disabled(void)
{
handler **file;
int error= 0;
DBUG_ASSERT(bitmap_is_set_all(&(m_part_info->lock_partitions)));
for (file= m_file; *file; file++)
{
if ((error= (*file)->indexes_are_disabled()))
break;
}
return error;
}
/**
Check/fix misplaced rows.
@param read_part_id Partition to check/fix.
@param repair If true, move misplaced rows to correct partition.
@return Operation status.
@retval 0 Success
@retval != 0 Error
*/
int ha_partition::check_misplaced_rows(uint read_part_id, bool do_repair)
{
int result= 0;
uint32 correct_part_id;
longlong func_value;
longlong num_misplaced_rows= 0;
DBUG_ENTER("ha_partition::check_misplaced_rows");
DBUG_ASSERT(m_file);
if (do_repair)
{
/* We must read the full row, if we need to move it! */
bitmap_set_all(table->read_set);
bitmap_set_all(table->write_set);
}
else
{
/* Only need to read the partitioning fields. */
bitmap_union(table->read_set, &m_part_info->full_part_field_set);
if (table->vcol_set)
bitmap_union(table->vcol_set, &m_part_info->full_part_field_set);
}
if ((result= m_file[read_part_id]->ha_rnd_init(1)))
DBUG_RETURN(result);
while (true)
{
if ((result= m_file[read_part_id]->ha_rnd_next(m_rec0)))
{
if (result == HA_ERR_RECORD_DELETED)
continue;
if (result != HA_ERR_END_OF_FILE)
break;
if (num_misplaced_rows > 0)
{
print_admin_msg(ha_thd(), MYSQL_ERRMSG_SIZE, "warning",
table_share->db.str, table->alias,
opt_op_name[REPAIR_PARTS],
"Moved %lld misplaced rows",
num_misplaced_rows);
}
/* End-of-file reached, all rows are now OK, reset result and break. */
result= 0;
break;
}
result= m_part_info->get_partition_id(m_part_info, &correct_part_id,
&func_value);
if (result)
break;
if (correct_part_id != read_part_id)
{
num_misplaced_rows++;
if (!do_repair)
{
/* Check. */
print_admin_msg(ha_thd(), MYSQL_ERRMSG_SIZE, "error",
table_share->db.str, table->alias,
opt_op_name[CHECK_PARTS],
"Found a misplaced row");
/* Break on first misplaced row! */
result= HA_ADMIN_NEEDS_UPGRADE;
break;
}
else
{
DBUG_PRINT("info", ("Moving row from partition %d to %d",
read_part_id, correct_part_id));
/*
Insert row into correct partition. Notice that there are no commit
for every N row, so the repair will be one large transaction!
*/
if ((result= m_file[correct_part_id]->ha_write_row(m_rec0)))
{
/*
We have failed to insert a row, it might have been a duplicate!
*/
char buf[MAX_KEY_LENGTH];
String str(buf,sizeof(buf),system_charset_info);
str.length(0);
if (result == HA_ERR_FOUND_DUPP_KEY)
{
str.append("Duplicate key found, "
"please update or delete the record:\n");
result= HA_ADMIN_CORRUPT;
}
m_err_rec= NULL;
append_row_to_str(str);
/*
If the engine supports transactions, the failure will be
rollbacked.
*/
if (!m_file[correct_part_id]->has_transactions())
{
/* Log this error, so the DBA can notice it and fix it! */
sql_print_error("Table '%-192s' failed to move/insert a row"
" from part %d into part %d:\n%s",
table->s->table_name.str,
read_part_id,
correct_part_id,
str.c_ptr_safe());
}
print_admin_msg(ha_thd(), MYSQL_ERRMSG_SIZE, "error",
table_share->db.str, table->alias,
opt_op_name[REPAIR_PARTS],
"Failed to move/insert a row"
" from part %d into part %d:\n%s",
read_part_id,
correct_part_id,
str.c_ptr_safe());
break;
}
/* Delete row from wrong partition. */
if ((result= m_file[read_part_id]->ha_delete_row(m_rec0)))
{
if (m_file[correct_part_id]->has_transactions())
break;
/*
We have introduced a duplicate, since we failed to remove it
from the wrong partition.
*/
char buf[MAX_KEY_LENGTH];
String str(buf,sizeof(buf),system_charset_info);
str.length(0);
m_err_rec= NULL;
append_row_to_str(str);
/* Log this error, so the DBA can notice it and fix it! */
sql_print_error("Table '%-192s': Delete from part %d failed with"
" error %d. But it was already inserted into"
" part %d, when moving the misplaced row!"
"\nPlease manually fix the duplicate row:\n%s",
table->s->table_name.str,
read_part_id,
result,
correct_part_id,
str.c_ptr_safe());
break;
}
}
}
}
int tmp_result= m_file[read_part_id]->ha_rnd_end();
DBUG_RETURN(result ? result : tmp_result);
}
#define KEY_PARTITIONING_CHANGED_STR \
"KEY () partitioning changed, please run:\n" \
"ALTER TABLE %s.%s ALGORITHM = INPLACE %s"
int ha_partition::check_for_upgrade(HA_CHECK_OPT *check_opt)
{
int error= HA_ADMIN_NEEDS_CHECK;
DBUG_ENTER("ha_partition::check_for_upgrade");
/*
This is called even without FOR UPGRADE,
if the .frm version is lower than the current version.
In that case return that it needs checking!
*/
if (!(check_opt->sql_flags & TT_FOR_UPGRADE))
DBUG_RETURN(error);
/*
Partitions will be checked for during their ha_check!
Check if KEY (sub)partitioning was used and any field's hash calculation
differs from 5.1, see bug#14521864.
*/
if (table->s->mysql_version < 50503 && // 5.1 table (<5.5.3)
((m_part_info->part_type == HASH_PARTITION && // KEY partitioned
m_part_info->list_of_part_fields) ||
(m_is_sub_partitioned && // KEY subpartitioned
m_part_info->list_of_subpart_fields)))
{
Field **field;
if (m_is_sub_partitioned)
{
field= m_part_info->subpart_field_array;
}
else
{
field= m_part_info->part_field_array;
}
for (; *field; field++)
{
switch ((*field)->real_type()) {
case MYSQL_TYPE_TINY:
case MYSQL_TYPE_SHORT:
case MYSQL_TYPE_LONG:
case MYSQL_TYPE_FLOAT:
case MYSQL_TYPE_DOUBLE:
case MYSQL_TYPE_NEWDECIMAL:
case MYSQL_TYPE_TIMESTAMP:
case MYSQL_TYPE_LONGLONG:
case MYSQL_TYPE_INT24:
case MYSQL_TYPE_TIME:
case MYSQL_TYPE_DATETIME:
case MYSQL_TYPE_YEAR:
case MYSQL_TYPE_NEWDATE:
case MYSQL_TYPE_ENUM:
case MYSQL_TYPE_SET:
{
THD *thd= ha_thd();
char *part_buf;
String db_name, table_name;
uint part_buf_len;
bool skip_generation= false;
partition_info::enum_key_algorithm old_algorithm;
old_algorithm= m_part_info->key_algorithm;
error= HA_ADMIN_FAILED;
append_identifier(ha_thd(), &db_name, table_share->db.str,
table_share->db.length);
append_identifier(ha_thd(), &table_name, table_share->table_name.str,
table_share->table_name.length);
if (m_part_info->key_algorithm != partition_info::KEY_ALGORITHM_NONE)
{
/*
Only possible when someone tampered with .frm files,
like during tests :)
*/
skip_generation= true;
}
m_part_info->key_algorithm= partition_info::KEY_ALGORITHM_51;
if (skip_generation ||
!(part_buf= generate_partition_syntax_for_frm(thd, m_part_info,
&part_buf_len,
NULL, NULL)) ||
print_admin_msg(thd, SQL_ADMIN_MSG_TEXT_SIZE + 1, "error",
table_share->db.str,
table->alias,
opt_op_name[CHECK_PARTS],
KEY_PARTITIONING_CHANGED_STR,
db_name.c_ptr_safe(),
table_name.c_ptr_safe(),
part_buf))
{
/* Error creating admin message (too long string?). */
print_admin_msg(thd, MYSQL_ERRMSG_SIZE, "error",
table_share->db.str, table->alias,
opt_op_name[CHECK_PARTS],
KEY_PARTITIONING_CHANGED_STR,
db_name.c_ptr_safe(), table_name.c_ptr_safe(),
"<old partition clause>, but add ALGORITHM = 1"
" between 'KEY' and '(' to change the metadata"
" without the need of a full table rebuild.");
}
m_part_info->key_algorithm= old_algorithm;
DBUG_RETURN(error);
}
default:
/* Not affected! */
;
}
}
}
DBUG_RETURN(error);
}
/**
Push an engine condition to the condition stack of the storage engine
for each partition.
@param cond Pointer to the engine condition to be pushed.
@return NULL Underlying engine will not return rows that
do not match the passed condition.
<> NULL 'Remainder' condition that the caller must use
to filter out records.
*/
const COND *ha_partition::cond_push(const COND *cond)
{
handler **file= m_file;
COND *res_cond= NULL;
DBUG_ENTER("ha_partition::cond_push");
do
{
if ((*file)->pushed_cond != cond)
{
if ((*file)->cond_push(cond))
res_cond= (COND *) cond;
else
(*file)->pushed_cond= cond;
}
} while (*(++file));
DBUG_RETURN(res_cond);
}
/**
Pop the top condition from the condition stack of the storage engine
for each partition.
*/
void ha_partition::cond_pop()
{
handler **file= m_file;
DBUG_ENTER("ha_partition::cond_pop");
do
{
(*file)->cond_pop();
} while (*(++file));
DBUG_VOID_RETURN;
}
struct st_mysql_storage_engine partition_storage_engine=
{ MYSQL_HANDLERTON_INTERFACE_VERSION };
maria_declare_plugin(partition)
{
MYSQL_STORAGE_ENGINE_PLUGIN,
&partition_storage_engine,
"partition",
"Mikael Ronstrom, MySQL AB",
"Partition Storage Engine Helper",
PLUGIN_LICENSE_GPL,
partition_initialize, /* Plugin Init */
NULL, /* Plugin Deinit */
0x0100, /* 1.0 */
NULL, /* status variables */
NULL, /* system variables */
"1.0", /* string version */
MariaDB_PLUGIN_MATURITY_STABLE /* maturity */
}
maria_declare_plugin_end;
#endif
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