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WL #2602, #2603, #2604

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Added new syntax for partition management
This commit is contained in:
pappa@c-4a09e253.1238-1-64736c10.cust.bredbandsbolaget.se
2005-08-19 10:26:05 -04:00
parent e9ce46a0bc
commit 5e91e260e6
13 changed files with 1358 additions and 177 deletions
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671
sql/sql_table.cc
View File

@ -45,6 +45,64 @@ static bool prepare_blob_field(THD *thd, create_field *sql_field);
static bool check_engine(THD *thd, const char *table_name,
enum db_type *new_engine);
/*
SYNOPSIS
write_bin_log()
thd Thread object
clear_error is clear_error to be called
RETURN VALUES
NONE
DESCRIPTION
Write the binlog if open, routine used in multiple places in this
file
*/
static void write_bin_log(THD *thd, bool clear_error)
{
if (mysql_bin_log.is_open())
{
if (clear_error)
thd->clear_error();
Query_log_event qinfo(thd, thd->query, thd->query_length, FALSE, FALSE);
mysql_bin_log.write(&qinfo);
}
}
/*
SYNOPSIS
abort_and_upgrade_lock()
thd Thread object
table Table object
db Database name
table_name Table name
old_lock_level Old lock level
RETURN VALUES
TRUE Failure
FALSE Success
DESCRIPTION
Remember old lock level (for possible downgrade later on), abort all
waiting threads and ensure that all keeping locks currently are
completed such that we own the lock exclusively and no other interaction
is ongoing.
*/
static bool abort_and_upgrade_lock(THD *thd, TABLE *table, const char *db,
const char *table_name,
uint *old_lock_level)
{
uint flags= RTFC_WAIT_OTHER_THREAD_FLAG | RTFC_CHECK_KILLED_FLAG;
DBUG_ENTER("abort_and_upgrade_locks");
*old_lock_level= table->reginfo.lock_type;
mysql_lock_abort(thd, table);
VOID(remove_table_from_cache(thd, db, table_name, flags));
if (thd->killed)
{
thd->no_warnings_for_error= 0;
DBUG_RETURN(TRUE);
}
DBUG_RETURN(FALSE);
}
/*
Build the path to a file for a table (or the base path that can
@ -317,13 +375,8 @@ int mysql_rm_table_part2(THD *thd, TABLE_LIST *tables, bool if_exists,
if (some_tables_deleted || tmp_table_deleted || !error)
{
query_cache_invalidate3(thd, tables, 0);
if (!dont_log_query && mysql_bin_log.is_open())
{
if (!error)
thd->clear_error();
Query_log_event qinfo(thd, thd->query, thd->query_length, FALSE, FALSE);
mysql_bin_log.write(&qinfo);
}
if (!dont_log_query)
write_bin_log(thd, !error);
}
unlock_table_names(thd, tables, (TABLE_LIST*) 0);
@ -1709,12 +1762,8 @@ bool mysql_create_table(THD *thd,const char *db, const char *table_name,
}
thd->tmp_table_used= 1;
}
if (!internal_tmp_table && mysql_bin_log.is_open())
{
thd->clear_error();
Query_log_event qinfo(thd, thd->query, thd->query_length, FALSE, FALSE);
mysql_bin_log.write(&qinfo);
}
if (!internal_tmp_table)
write_bin_log(thd, TRUE);
error= FALSE;
end:
@ -2784,12 +2833,7 @@ bool mysql_create_like_table(THD* thd, TABLE_LIST* table,
}
// Must be written before unlock
if (mysql_bin_log.is_open())
{
thd->clear_error();
Query_log_event qinfo(thd, thd->query, thd->query_length, FALSE, FALSE);
mysql_bin_log.write(&qinfo);
}
write_bin_log(thd, TRUE);
res= FALSE;
goto err;
@ -2895,11 +2939,7 @@ mysql_discard_or_import_tablespace(THD *thd,
error=1;
if (error)
goto err;
if (mysql_bin_log.is_open())
{
Query_log_event qinfo(thd, thd->query, thd->query_length, FALSE, FALSE);
mysql_bin_log.write(&qinfo);
}
write_bin_log(thd, FALSE);
err:
close_thread_tables(thd);
thd->tablespace_op=FALSE;
@ -3301,7 +3341,10 @@ bool mysql_alter_table(THD *thd,char *new_db, char *new_name,
enum db_type old_db_type,new_db_type;
uint need_copy_table= 0;
#ifdef HAVE_PARTITION_DB
bool online_add_empty_partition= FALSE;
bool online_drop_partition= FALSE;
bool partition_changed= FALSE;
enum db_type default_engine_type;
#endif
DBUG_ENTER("mysql_alter_table");
@ -3378,66 +3421,421 @@ bool mysql_alter_table(THD *thd,char *new_db, char *new_name,
old_db_type= table->s->db_type;
if (create_info->db_type == DB_TYPE_DEFAULT)
create_info->db_type= old_db_type;
#ifdef HAVE_PARTITION_DB
/*
When thd->lex->part_info has a reference to a partition_info the
ALTER TABLE contained a definition of a partitioning.
Case I:
If there was a partition before and there is a new one defined.
We use the new partitioning. The new partitioning is already
defined in the correct variable so no work is needed to
accomplish this.
We do however need to update partition_changed to ensure that not
only the frm file is changed in the ALTER TABLE command.
Case IIa:
There was a partitioning before and there is no new one defined.
Also the user has not specified an explicit engine to use.
We use the old partitioning also for the new table. We do this
by assigning the partition_info from the table loaded in
open_ltable to the partition_info struct used by mysql_create_table
later in this method.
Case IIb:
There was a partitioning before and there is no new one defined.
The user has specified an explicit engine to use.
Since the user has specified an explicit engine to use we override
the old partitioning info and create a new table using the specified
engine. This is the reason for the extra check if old and new engine
is equal.
In this case the partition also is changed.
Case III:
There was no partitioning before altering the table, there is
partitioning defined in the altered table. Use the new partitioning.
No work needed since the partitioning info is already in the
correct variable.
Also here partition has changed and thus a new table must be
created.
Case IV:
There was no partitioning before and no partitioning defined. Obviously
no work needed.
*/
if (table->s->part_info)
We need to handle both partition management command such as Add Partition
and others here as well as an ALTER TABLE that completely changes the
partitioning and yet others that don't change anything at all. We start
by checking the partition management variants and then check the general
change patterns.
*/
if (alter_info->flags & (ALTER_ADD_PARTITION +
ALTER_DROP_PARTITION + ALTER_COALESCE_PARTITION +
ALTER_REORGANISE_PARTITION))
{
if (!thd->lex->part_info &&
create_info->db_type == old_db_type)
thd->lex->part_info= table->s->part_info;
partition_info *tab_part_info= table->s->part_info;
if (!tab_part_info)
{
my_error(ER_PARTITION_MGMT_ON_NONPARTITIONED, MYF(0));
DBUG_RETURN(TRUE);
}
{
List_iterator<partition_element> t_it(tab_part_info->partitions);
partition_element *t_part_elem= t_it++;
if (is_sub_partitioned(tab_part_info))
{
List_iterator<partition_element> s_it(t_part_elem->subpartitions);
t_part_elem= s_it++;
}
default_engine_type= t_part_elem->engine_type;
}
/*
We are going to manipulate the partition info on the table object
so we need to ensure that the data structure of the table object
is freed by setting version to 0.
*/
table->s->version= 0L;
if (alter_info->flags == ALTER_ADD_PARTITION)
{
/*
We start by moving the new partitions to the list of temporary
partitions. We will then check that the new partitions fit in the
partitioning scheme as currently set-up.
Partitions are always added at the end in ADD PARTITION.
*/
partition_info *alt_part_info= thd->lex->part_info;
uint no_new_partitions= alt_part_info->no_parts;
uint no_orig_partitions= tab_part_info->no_parts;
uint check_total_partitions= no_new_partitions + no_orig_partitions;
uint new_total_partitions= check_total_partitions;
/*
We allow quite a lot of values to be supplied by defaults, however we
must know the number of new partitions in this case.
*/
if (no_new_partitions == 0)
{
my_error(ER_ADD_PARTITION_NO_NEW_PARTITION, MYF(0));
DBUG_RETURN(TRUE);
}
if (is_sub_partitioned(tab_part_info))
{
if (alt_part_info->no_subparts == 0)
alt_part_info->no_subparts= tab_part_info->no_subparts;
else if (alt_part_info->no_subparts != tab_part_info->no_subparts)
{
my_error(ER_ADD_PARTITION_SUBPART_ERROR, MYF(0));
DBUG_RETURN(TRUE);
}
check_total_partitions= new_total_partitions*
alt_part_info->no_subparts;
}
if (check_total_partitions > MAX_PARTITIONS)
{
my_error(ER_TOO_MANY_PARTITIONS_ERROR, MYF(0));
DBUG_RETURN(TRUE);
}
alt_part_info->part_type= tab_part_info->part_type;
if (set_up_defaults_for_partitioning(alt_part_info,
table->file,
(ulonglong)0ULL,
tab_part_info->no_parts))
{
DBUG_RETURN(TRUE);
}
/*
Need to concatenate the lists here to make it possible to check the
partition info for correctness using check_partition_info
*/
{
List_iterator<partition_element> alt_it(alt_part_info->partitions);
uint part_count= 0;
do
{
partition_element *part_elem= alt_it++;
tab_part_info->partitions.push_back(part_elem);
tab_part_info->temp_partitions.push_back(part_elem);
} while (++part_count < no_new_partitions);
tab_part_info->no_parts+= no_new_partitions;
}
{
List_iterator<partition_element> tab_it(tab_part_info->partitions);
partition_element *part_elem= tab_it++;
if (is_sub_partitioned(tab_part_info))
{
List_iterator<partition_element> sub_it(part_elem->subpartitions);
part_elem= sub_it++;
}
if (check_partition_info(tab_part_info, part_elem->engine_type,
table->file, (ulonglong)0ULL))
{
DBUG_RETURN(TRUE);
}
}
create_info->db_type= DB_TYPE_PARTITION_DB;
thd->lex->part_info= tab_part_info;
if (table->file->alter_table_flags() & HA_ONLINE_ADD_EMPTY_PARTITION &&
(tab_part_info->part_type == RANGE_PARTITION ||
tab_part_info->part_type == LIST_PARTITION))
{
/*
For range and list partitions add partition is simply adding a new
empty partition to the table. If the handler support this we will
use the simple method of doing this. In this case we need to break
out the new partitions from the list again and only keep them in the
temporary list. Added partitions are always added at the end.
*/
{
List_iterator<partition_element> tab_it(tab_part_info->partitions);
uint part_count= 0;
do
{
tab_it++;
} while (++part_count < no_orig_partitions);
do
{
tab_it++;
tab_it.remove();
} while (++part_count < new_total_partitions);
}
tab_part_info->no_parts-= no_new_partitions;
online_add_empty_partition= TRUE;
}
else
{
tab_part_info->temp_partitions.empty();
}
}
else if (alter_info->flags == ALTER_DROP_PARTITION)
{
/*
Drop a partition from a range partition and list partitioning is
always safe and can be made more or less immediate. It is necessary
however to ensure that the partition to be removed is safely removed
and that REPAIR TABLE can remove the partition if for some reason the
command to drop the partition failed in the middle.
*/
uint part_count= 0;
uint no_parts_dropped= alter_info->partition_names.elements;
uint no_parts_found= 0;
List_iterator<partition_element> part_it(tab_part_info->partitions);
if (!(tab_part_info->part_type == RANGE_PARTITION ||
tab_part_info->part_type == LIST_PARTITION))
{
my_error(ER_ONLY_ON_RANGE_LIST_PARTITION, MYF(0), "DROP");
DBUG_RETURN(TRUE);
}
if (no_parts_dropped >= tab_part_info->no_parts)
{
my_error(ER_DROP_LAST_PARTITION, MYF(0));
DBUG_RETURN(TRUE);
}
do
{
partition_element *part_elem= part_it++;
if (is_partition_in_list(part_elem->partition_name,
alter_info->partition_names))
{
/*
Remove the partition from the list and put it instead in the
list of temporary partitions with a new state.
*/
no_parts_found++;
part_elem->part_state= PART_IS_DROPPED;
}
} while (++part_count < tab_part_info->no_parts);
if (no_parts_found != no_parts_dropped)
{
my_error(ER_DROP_PARTITION_NON_EXISTENT, MYF(0));
DBUG_RETURN(TRUE);
}
if (!(table->file->alter_table_flags() & HA_ONLINE_DROP_PARTITION))
{
my_error(ER_DROP_PARTITION_FAILURE, MYF(0));
DBUG_RETURN(TRUE);
}
if (table->file->is_fk_defined_on_table_or_index(MAX_KEY))
{
my_error(ER_DROP_PARTITION_WHEN_FK_DEFINED, MYF(0));
DBUG_RETURN(TRUE);
}
/*
This code needs set-up of structures needed by mysql_create_table
before it is called and thus we only set a boolean variable to be
checked later down in the code when all needed data structures are
prepared.
*/
online_drop_partition= TRUE;
}
else if (alter_info->flags == ALTER_COALESCE_PARTITION)
{
/*
In this version COALESCE PARTITION is implemented by simply removing
a partition from the table and using the normal ALTER TABLE code
and ensuring that copy to a new table occurs. Later on we can optimise
this function for Linear Hash partitions. In that case we can avoid
reorganising the entire table. For normal hash partitions it will
be a complete reorganise anyways so that can only be made on-line
if it still uses a copy table.
*/
uint part_count= 0;
uint no_parts_coalesced= alter_info->no_parts;
uint no_parts_remain= tab_part_info->no_parts - no_parts_coalesced;
List_iterator<partition_element> part_it(tab_part_info->partitions);
if (tab_part_info->part_type != HASH_PARTITION)
{
my_error(ER_COALESCE_ONLY_ON_HASH_PARTITION, MYF(0));
DBUG_RETURN(TRUE);
}
if (no_parts_coalesced == 0)
{
my_error(ER_COALESCE_PARTITION_NO_PARTITION, MYF(0));
DBUG_RETURN(TRUE);
}
if (no_parts_coalesced >= tab_part_info->no_parts)
{
my_error(ER_DROP_LAST_PARTITION, MYF(0));
DBUG_RETURN(TRUE);
}
do
{
part_it++;
if (++part_count > no_parts_remain)
part_it.remove();
} while (part_count < tab_part_info->no_parts);
tab_part_info->no_parts= no_parts_remain;
}
else if (alter_info->flags == ALTER_REORGANISE_PARTITION)
{
/*
Reorganise partitions takes a number of partitions that are next
to each other (at least for RANGE PARTITIONS) and then uses those
to create a set of new partitions. So data is copied from those
partitions into the new set of partitions. Those new partitions
can have more values in the LIST value specifications or less both
are allowed. The ranges can be different but since they are
changing a set of consecutive partitions they must cover the same
range as those changed from.
This command can be used on RANGE and LIST partitions.
*/
uint no_parts_reorged= alter_info->partition_names.elements;
uint no_parts_new= thd->lex->part_info->partitions.elements;
partition_info *alt_part_info= thd->lex->part_info;
uint check_total_partitions;
if (no_parts_reorged > tab_part_info->no_parts)
{
my_error(ER_REORG_PARTITION_NOT_EXIST, MYF(0));
DBUG_RETURN(TRUE);
}
if (!(tab_part_info->part_type == RANGE_PARTITION ||
tab_part_info->part_type == LIST_PARTITION))
{
my_error(ER_ONLY_ON_RANGE_LIST_PARTITION, MYF(0), "REORGANISE");
DBUG_RETURN(TRUE);
}
if (is_partitions_in_table(alt_part_info, tab_part_info))
{
my_error(ER_SAME_NAME_PARTITION, MYF(0));
DBUG_RETURN(TRUE);
}
check_total_partitions= tab_part_info->no_parts + no_parts_new;
check_total_partitions-= no_parts_reorged;
if (check_total_partitions > MAX_PARTITIONS)
{
my_error(ER_TOO_MANY_PARTITIONS_ERROR, MYF(0));
DBUG_RETURN(TRUE);
}
{
List_iterator<partition_element> tab_it(tab_part_info->partitions);
uint part_count= 0;
bool found_first= FALSE, found_last= FALSE;
uint drop_count= 0;
longlong tab_max_range, alt_max_range;
do
{
partition_element *part_elem= tab_it++;
if (is_partition_in_list(part_elem->partition_name,
alter_info->partition_names))
{
drop_count++;
tab_max_range= part_elem->range_value;
if (!found_first)
{
uint alt_part_count= 0;
found_first= TRUE;
List_iterator<partition_element> alt_it(alt_part_info->partitions);
do
{
partition_element *alt_part_elem= alt_it++;
alt_max_range= alt_part_elem->range_value;
if (alt_part_count == 0)
tab_it.replace(alt_part_elem);
else
tab_it.after(alt_part_elem);
} while (++alt_part_count < no_parts_new);
}
else if (found_last)
{
my_error(ER_CONSECUTIVE_REORG_PARTITIONS, MYF(0));
DBUG_RETURN(TRUE);
}
else
tab_it.remove();
}
else
{
if (found_first)
found_last= TRUE;
}
} while (++part_count < tab_part_info->no_parts);
if (drop_count != no_parts_reorged)
{
my_error(ER_DROP_PARTITION_NON_EXISTENT, MYF(0));
DBUG_RETURN(TRUE);
}
if (tab_part_info->part_type == RANGE_PARTITION &&
alt_max_range > tab_max_range)
{
my_error(ER_REORG_OUTSIDE_RANGE, MYF(0));
DBUG_RETURN(TRUE);
}
}
}
partition_changed= TRUE;
create_info->db_type= DB_TYPE_PARTITION_DB;
thd->lex->part_info= tab_part_info;
if (alter_info->flags == ALTER_ADD_PARTITION ||
alter_info->flags == ALTER_REORGANISE_PARTITION)
{
if (check_partition_info(tab_part_info, default_engine_type,
table->file, (ulonglong)0ULL))
{
DBUG_RETURN(TRUE);
}
}
}
if (thd->lex->part_info)
else
{
/*
Need to cater for engine types that can handle partition without
using the partition handler.
When thd->lex->part_info has a reference to a partition_info the
ALTER TABLE contained a definition of a partitioning.
Case I:
If there was a partition before and there is a new one defined.
We use the new partitioning. The new partitioning is already
defined in the correct variable so no work is needed to
accomplish this.
We do however need to update partition_changed to ensure that not
only the frm file is changed in the ALTER TABLE command.
Case IIa:
There was a partitioning before and there is no new one defined.
Also the user has not specified an explicit engine to use.
We use the old partitioning also for the new table. We do this
by assigning the partition_info from the table loaded in
open_ltable to the partition_info struct used by mysql_create_table
later in this method.
Case IIb:
There was a partitioning before and there is no new one defined.
The user has specified an explicit engine to use.
Since the user has specified an explicit engine to use we override
the old partitioning info and create a new table using the specified
engine. This is the reason for the extra check if old and new engine
is equal.
In this case the partition also is changed.
Case III:
There was no partitioning before altering the table, there is
partitioning defined in the altered table. Use the new partitioning.
No work needed since the partitioning info is already in the
correct variable.
Also here partition has changed and thus a new table must be
created.
Case IV:
There was no partitioning before and no partitioning defined.
Obviously no work needed.
*/
if (thd->lex->part_info != table->s->part_info)
partition_changed= TRUE;
thd->lex->part_info->default_engine_type= create_info->db_type;
create_info->db_type= DB_TYPE_PARTITION_DB;
if (table->s->part_info)
{
if (!thd->lex->part_info &&
create_info->db_type == old_db_type)
thd->lex->part_info= table->s->part_info;
}
if (thd->lex->part_info)
{
/*
Need to cater for engine types that can handle partition without
using the partition handler.
*/
if (thd->lex->part_info != table->s->part_info)
partition_changed= TRUE;
thd->lex->part_info->default_engine_type= create_info->db_type;
create_info->db_type= DB_TYPE_PARTITION_DB;
}
}
#endif
if (check_engine(thd, new_name, &create_info->db_type))
@ -3503,12 +3901,7 @@ bool mysql_alter_table(THD *thd,char *new_db, char *new_name,
}
if (!error)
{
if (mysql_bin_log.is_open())
{
thd->clear_error();
Query_log_event qinfo(thd, thd->query, thd->query_length, FALSE, FALSE);
mysql_bin_log.write(&qinfo);
}
write_bin_log(thd, TRUE);
if (do_send_ok)
send_ok(thd);
}
@ -3824,6 +4217,100 @@ bool mysql_alter_table(THD *thd,char *new_db, char *new_name,
if (!need_copy_table)
create_info->frm_only= 1;
if (partition_changed)
{
if (online_drop_partition)
{
/*
Now after all checks and setting state on dropped partitions we can
start the actual dropping of the partitions.
1) Lock table in TL_WRITE_ONLY to ensure all other accesses on table
are completed and no new ones are started until we have changed
the frm file.
2) Write the new frm file where state of dropped partitions is
changed to PART_IS_DROPPED
3) Perform the actual drop of the partition using the handler of the
table.
4) Write a new frm file of the table where the partitions are dropped
from the table.
*/
uint old_lock_type;
partition_info *part_info= table->s->part_info;
char path[FN_REFLEN+1];
uint db_options= 0, key_count, syntax_len;
KEY *key_info_buffer;
char *part_syntax_buf;
VOID(pthread_mutex_lock(&LOCK_open));
if (abort_and_upgrade_lock(thd, table, db, table_name, &old_lock_type))
{
DBUG_RETURN(TRUE);
}
VOID(pthread_mutex_unlock(&LOCK_open));
mysql_prepare_table(thd, create_info, &create_list,
&key_list, /*tmp_table*/ 0, &db_options,
table->file, &key_info_buffer, &key_count,
/*select_field_count*/ 0);
if (!(part_syntax_buf= generate_partition_syntax(part_info,
&syntax_len,
TRUE)))
{
DBUG_RETURN(TRUE);
}
part_info->part_info_string= part_syntax_buf;
part_info->part_info_len= syntax_len;
build_table_path(path, sizeof(path), db, table_name, reg_ext);
if (mysql_create_frm(thd, path, db, table_name, create_info,
create_list, key_count, key_info_buffer,
table->file))
{
DBUG_RETURN(TRUE);
}
thd->lex->part_info= part_info;
build_table_path(path, sizeof(path), db, table_name, "");
if (table->file->drop_partitions(path))
{
DBUG_RETURN(TRUE);
}
{
List_iterator<partition_element> part_it(part_info->partitions);
uint i= 0, remove_count= 0;
do
{
partition_element *part_elem= part_it++;
if (is_partition_in_list(part_elem->partition_name,
alter_info->partition_names))
{
part_it.remove();
remove_count++;
}
} while (++i < part_info->no_parts);
part_info->no_parts-= remove_count;
}
if (!(part_syntax_buf= generate_partition_syntax(part_info,
&syntax_len,
TRUE)))
{
DBUG_RETURN(TRUE);
}
part_info->part_info_string= part_syntax_buf;
part_info->part_info_len= syntax_len;
build_table_path(path, sizeof(path), db, table_name, reg_ext);
if (mysql_create_frm(thd, path, db, table_name, create_info,
create_list, key_count, key_info_buffer,
table->file) ||
table->file->create_handler_files(path))
{
DBUG_RETURN(TRUE);
}
thd->proc_info="end";
write_bin_log(thd, FALSE);
send_ok(thd);
DBUG_RETURN(FALSE);
}
}
/*
Handling of symlinked tables:
If no rename:
@ -3949,12 +4436,7 @@ bool mysql_alter_table(THD *thd,char *new_db, char *new_name,
my_free((gptr) new_table,MYF(0));
goto err;
}
if (mysql_bin_log.is_open())
{
thd->clear_error();
Query_log_event qinfo(thd, thd->query, thd->query_length, FALSE, FALSE);
mysql_bin_log.write(&qinfo);
}
write_bin_log(thd, TRUE);
goto end_temporary;
}
@ -4085,15 +4567,14 @@ bool mysql_alter_table(THD *thd,char *new_db, char *new_name,
goto err;
}
thd->proc_info="end";
if (mysql_bin_log.is_open())
{
thd->clear_error();
Query_log_event qinfo(thd, thd->query, thd->query_length, FALSE, FALSE);
mysql_bin_log.write(&qinfo);
}
write_bin_log(thd, TRUE);
VOID(pthread_cond_broadcast(&COND_refresh));
VOID(pthread_mutex_unlock(&LOCK_open));
#ifdef HAVE_BERKELEY_DB
/*
TODO RONM: This problem needs to handled for Berkeley DB partitions
as well
*/
if (old_db_type == DB_TYPE_BERKELEY_DB)
{
/*