Added capability to create a trigger associated with several trigger
events. For this goal, the syntax of the CREATE TRIGGER statement
was extended to support the syntax structure { event [ OR ... ] }
for the `trigger_event` clause. Since one trigger will be able to
handle several events it should be provided a way to determine what
kind of event is handled on execution of a trigger. For this goal
support of the clauses INSERTING, UPDATING , DELETING was added by
this patch. These clauses can be used inside a trigger body to detect
what kind of trigger action is currently processed using the following
boilerplate:
IF INSERTING THEN ...
ELSIF UPDATING THEN ...
ELSIF DELETING THEN ...
In case one of the clauses INSERTING, UPDATING, DELETING specified in
a trigger's body not matched with a trigger event type, the error
ER_INCOMPATIBLE_EVENT_FLAG is emitted.
After this patch be pushed, one Trigger object will be associated with
several trigger events. It means that the array
Table_triggers_list::triggers
can contain several pointers to the same Trigger object in array members
corresponding to different events. Moreover, support of several trigger
events for the same trigger requires that the data members `next` and
`action_order` of the Trigger class be converted to arrays to store
relating information per trigger event base.
Ability to specify the same trigger for different event types results in
necessity to handle invalid cases on execution of the multi-event
trigger, when the OLD or NEW qualifiers doesn't match a current event
type against that the trigger is run. The clause OLD should produces
the NULL value for INSERT event, whereas the clause NEW should produce
the NULL value for DELETE event.
This patch adds support for SYS_REFCURSOR (a weakly typed cursor)
for both sql_mode=ORACLE and sql_mode=DEFAULT.
Works as a regular stored routine variable, parameter and return value:
- can be passed as an IN parameter to stored functions and procedures
- can be passed as an INOUT and OUT parameter to stored procedures
- can be returned from a stored function
Note, strongly typed REF CURSOR will be added separately.
Note, to maintain dependencies easier, some parts of sql_class.h
and item.h were moved to new header files:
- select_results.h:
class select_result_sink
class select_result
class select_result_interceptor
- sp_cursor.h:
class sp_cursor_statistics
class sp_cursor
- sp_rcontext_handler.h
class Sp_rcontext_handler and its descendants
The implementation consists of the following parts:
- A new class sp_cursor_array deriving from Dynamic_array
- A new class Statement_rcontext which contains data shared
between sub-statements of a compound statement.
It has a member m_statement_cursors of the sp_cursor_array data type,
as well as open cursor counter. THD inherits from Statement_rcontext.
- A new data type handler Type_handler_sys_refcursor in plugins/type_cursor/
It is designed to store uint16 references -
positions of the cursor in THD::m_statement_cursors.
- Type_handler_sys_refcursor suppresses some derived numeric features.
When a SYS_REFCURSOR variable is used as an integer an error is raised.
- A new abstract class sp_instr_fetch_cursor. It's needed to share
the common code between "OPEN cur" (for static cursors) and
"OPER cur FOR stmt" (for SYS_REFCURSORs).
- New sp_instr classes:
* sp_instr_copen_by_ref - OPEN sys_ref_curor FOR stmt;
* sp_instr_cfetch_by_ref - FETCH sys_ref_cursor INTO targets;
* sp_instr_cclose_by_ref - CLOSE sys_ref_cursor;
* sp_instr_destruct_variable - to destruct SYS_REFCURSOR variables when
the execution goes out of the BEGIN..END block
where SYS_REFCURSOR variables are declared.
- New methods in LEX:
* sp_open_cursor_for_stmt - handles "OPEN sys_ref_cursor FOR stmt".
* sp_add_instr_fetch_cursor - "FETCH cur INTO targets" for both
static cursors and SYS_REFCURSORs.
* sp_close - handles "CLOSE cur" both for static cursors and SYS_REFCURSORs.
- Changes in cursor functions to handle both static cursors and SYS_REFCURSORs:
* Item_func_cursor_isopen
* Item_func_cursor_found
* Item_func_cursor_notfound
* Item_func_cursor_rowcount
- A new system variable @@max_open_cursors - to limit the number
of cursors (static and SYS_REFCURSORs) opened at the same time.
Its allowed range is [0-65536], with 50 by default.
- A new virtual method Type_handler::can_return_bool() telling
if calling item->val_bool() is allowed for Items of this data type,
or if otherwise the "Illegal parameter for operation" error should be raised
at fix_fields() time.
- New methods in Sp_rcontext_handler:
* get_cursor()
* get_cursor_by_ref()
- A new class Sp_rcontext_handler_statement to handle top level statement
wide cursors which are shared by all substatements.
- A new virtual method expr_event_handler() in classes Item and Field.
It's needed to close (and make available for a new OPEN)
unused THD::m_statement_cursors elements which do not have any references
any more. It can happen in various moments in time, e.g.
* after evaluation parameters of an SQL routine
* after assigning a cursor expression into a SYS_REFCURSOR variable
* when leaving a BEGIN..END block with SYS_REFCURSOR variables
* after setting OUT/INOUT routine actual parameters from formal
parameters.
wait_for_prior_commit() can be called multiple times per event group,
only do my_error() the first time the call fails.
Remove redundant set_overwrite_status() calls.
Signed-off-by: Kristian Nielsen <knielsen@knielsen-hq.org>
Reviewed-by: Monty <monty@mariadb.org>
It was not possible to use a package body variable as a
fetch target:
CREATE PACKAGE BODY pkg AS
vc INT := 0;
FUNCTION f1 RETURN INT AS
CURSOR cur IS SELECT 1 AS c FROM DUAL;
BEGIN
OPEN cur;
FETCH cur INTO vc; -- this returned "Undeclared variable: vc" error.
CLOSE cur;
RETURN vc;
END;
END;
FETCH assumed that all fetch targets reside of the same sp_rcontext
instance with the cursor. This patch fixes the problem.
Now a cursor and its fetch target can reside in different sp_rcontext
instances.
Details:
- Adding a helper class sp_rcontext_addr
(a combination of Sp_rcontext_handler pointer and an offset in the rcontext)
- Adding a new class sp_fetch_target deriving from sp_rcontext_addr.
Fetch targets in "FETCH cur INTO target1, target2 ..." are now collected
into this structure instead of sp_variable.
sp_variable cannot be used any more to store fetch targets,
because it does not have a pointer to Sp_rcontext_handler
(it only has the current rcontext offset).
- Removing members sp_instr_set members m_rcontext_handler and m_offset.
Deriving sp_instr_set from sp_rcontext_addr instead.
- Renaming sp_instr_cfetch member "List<sp_variable> m_varlist"
to "List<sp_fetch_target> m_fetch_target_list".
- Fixing LEX::sp_add_cfetch() to return the pointer to the
created sp_fetch_target instance (instead of returning bool).
This helps to make the grammar in sql_yacc.c simpler
- Renaming LEX::sp_add_cfetch() to LEX::sp_add_instr_cfetch(),
as `if(sp_add_cfetch())` changed its meaning to the opposite,
to avoid automatic wrong merge from earlier versions.
- Chaning the "List<sp_variable> *vars" parameter to sp_cursor::fetch
to have the data type "List<sp_fetch_target> *".
- Changing the data type of "List<sp_variable> &vars" in
sp_cursor::Select_fetch_into_spvars::send_data_to_variable_list()
to "List<sp_fetch_target> &".
- Adding THD helper methods get_rcontext() and get_variable().
- Moving the code from sql_yacc.yy into a new LEX method
LEX::make_fetch_target().
- Simplifying the grammar in sql_yacc.yy using the new LEX method.
Changing the data type of the bison rule sp_fetch_list from "void"
to "List<sp_fetch_target> *".
* rpl.rpl_system_versioning_partitions updated for MDEV-32188
* innodb.row_size_error_log_warnings_3 changed error for MDEV-33658
(checks are done in a different order)
Cannot add a foreign key on a table with a long UNIQUE multi-column index, that
contains a foreign key as a prefix.
Check that index algorithms match during the "generated" keys duplicate removal.
mysql_prepare_create_table: Extract a Key initialization part that
relates to length calculation and long unique index designation.
append_system_key_parts call also moves there.
Move this initialization before the duplicate elimination.
Extract WITHOUT OVERPLAPS check into a separate function. It had to be moved
earlier in the code to preserve the order of the error checks, as in the tests.
InnoDB transactions may be reused after committed:
- when taken from the transaction pool
- during a DDL operation execution
In this case wsrep flag on trx object is cleared, which may cause wrong
execution logic afterwards (wsrep-related hooks are not run).
Make trx->wsrep flag initialize from THD object only once on InnoDB transaction
start and don't change it throughout the transaction's lifetime.
The flag is reset at commit time as before.
Unconditionally set wsrep=OFF for THD objects that represent InnoDB background
threads.
Make Wsrep_schema::store_view() operate in its own transaction.
Fix streaming replication transactions' fragments rollback to not switch
THD->wsrep value during transaction's execution
(use THD->wsrep_ignore_table as a workaround).
Signed-off-by: Julius Goryavsky <julius.goryavsky@mariadb.com>
The problems were that:
1) resources was freed "asimetric" normal execution in send_eof,
in case of error in destructor.
2) destructor was not called in case of SP for result objects.
(so if the last SP execution ended with error resorces was not
freeded on reinit before execution (cleanup() called before next
execution) and destructor also was not called due to lack of
delete call for the object)
Result cleanup() renamed to reset_for_next_ps_execution() to better
reflect function().
All result method revised and freeing resources made "symetric".
Destructor of result object called for SP.
Added skipped invalidation in case of error in insert.
Removed misleading naming of reset(thd) (could be mixed with
with reset()).
This commit updates default memory allocations size used with MEM_ROOT
objects to minimize the number of calls to malloc().
Changes:
- Updated MEM_ROOT block sizes in sql_const.h
- Updated MALLOC_OVERHEAD to also take into account the extra memory
allocated by my_malloc()
- Updated init_alloc_root() to only take MALLOC_OVERHEAD into account as
buffer size, not MALLOC_OVERHEAD + sizeof(USED_MEM).
- Reset mem_root->first_block_usage if and only if first block was used.
- Increase MEM_ROOT buffers sized used by my_load_defaults, plugin_init,
Create_tmp_table, allocate_table_share, TABLE and TABLE_SHARE.
This decreases number of malloc calls during queries.
- Use a small buffer for THD->main_mem_root in THD::THD. This avoids
multiple malloc() call for new connections.
I tried the above changes on a complex select query with 12 tables.
The following shows the number of extra allocations that where used
to increase the size of the MEM_ROOT buffers.
Original code:
- Connection to MariaDB: 9 allocations
- First query run: 146 allocations
- Second query run: 24 allocations
Max memory allocated for thd when using with heap table: 61,262,408
Max memory allocated for thd when using Aria tmp table: 419,464
After changes:
Connection to MariaDB: 0 allocations
- First run: 25 allocations
- Second run: 7 allocations
Max memory allocated for thd when using with heap table: 61,347,424
Max memory allocated for thd when using Aria table: 529,168
The new code uses slightly more memory, but avoids memory fragmentation
and is slightly faster thanks to much fewer calls to malloc().
Reviewed-by: Sergei Golubchik <serg@mariadb.org>
Added Query_time (total time spent running queries) to status_variables.
Other things:
- Added SHOW_MICROSECOND_STATUS type that shows an ulonglong variable
in microseconds converted to a double (in seconds).
- Changed Busy_time and Cpu_time to use SHOW_MICROSECOND_STATUS, which
simplified the code and avoids some double divisions for each query.
Reviewed-by: Sergei Golubchik <serg@mariadb.org>
Partial commit of the greater MDEV-34348 scope.
MDEV-34348: MariaDB is violating clang-16 -Wcast-function-type-strict
Change the type of my_hash_get_key to:
1) Return const
2) Change the context parameter to be const void*
Also fix casting in hash adjacent areas.
Reviewed By:
============
Marko Mäkelä <marko.makela@mariadb.com>
into a separate transaction_participant structure
handlerton inherits it, so handlerton itself doesn't change.
but entities that only need to participate in a transaction,
like binlog or online alter log, use a transaction_participant
and no longer need to pretend to be a full-blown but invisible
storage engine which doesn't support create table.
create templates
thd->alloc<X>(n) to use instead of (X*)thd->alloc(sizeof(X)*n)
and the same for thd->calloc(). By the default the type is char,
so old usage of thd->alloc(size) works too.
When strict mode is enabled, all warnings during `INSERT` are
converted to errors regardless of their actual severity.
`WARN_SORTING_ON_TRUNCATED_LENGTH` is not considered severe enough
to be elevated to the ERROR level, and this commit fixes that
lock_rec_unlock_unmodified() is executed either under lock_sys.wr_lock()
or under a combination of lock_sys.rd_lock() + record locks hash table
cell latch. It also requests page latch to check if locked records were
changed by the current transaction or not.
Usually InnoDB requests page latch to find the certain record on the
page, and then requests lock_sys and/or record lock hash cell latch to
request record lock. lock_rec_unlock_unmodified() requests the latches
in the opposite order, what causes deadlocks. One of the possible
scenario for the deadlock is the following:
thread 1 - lock_rec_unlock_unmodified() is invoked under locks hash table
cell latch, the latch is acquired;
thread 2 - purge thread acquires page latch and tries to remove
delete-marked record, it invokes lock_update_delete(), which
requests locks hash table cell latch, held by thread 1;
thread 1 - requests page latch, held by thread 2.
To fix it we need to release lock_sys.latch and/or lock hash cell latch,
acquire page latch and re-acquire lock_sys related latches.
When lock_sys.latch and/or lock hash cell latch are released in
lock_release_on_prepare() and lock_release_on_prepare_try(), the page on
which the current lock is held, can be merged. In this case the bitmap
of the current lock must be cleared, and the new lock must be added to
the end of trx->lock.trx_locks list, or bitmap of already existing lock
must be changed.
The new field trx_lock_t::set_nth_bit_calls indicates if new locks
(bits in existing lock bitmaps or new lock objects) were created during
the period when lock_sys was released in trx->lock.trx_locks list
iteration loop in lock_release_on_prepare() or
lock_release_on_prepare_try(). And, if so, we traverse the list again.
The block can be freed during pages merging, what causes assertion
failure in buf_page_get_gen(), as btr_block_get() passes BUF_GET as page
get mode to it. That's why page_get_mode parameter was added to
btr_block_get() to pass BUF_GET_POSSIBLY_FREED from
lock_release_on_prepare() and lock_release_on_prepare_try() to
buf_page_get_gen().
As searching for id of trx, which modified secondary index record, is
quite expensive operation, restrict its usage for master. System variable
was added to remove the restriction for testing simplifying. The
variable exists only either for debug build or for build with
-DINNODB_ENABLE_XAP_UNLOCK_UNMODIFIED_FOR_PRIMARY option to increase the
probability of catching bugs for release build with RQG.
Note that the code, which does primary index lookup to find out what
transaction modified secondary index record, is necessary only when
there is no primary key and no unique secondary key on replica with row
based replication, because only in this case extra X locks on unmodified
records can be set during scan phase.
Reviewed by Marko Mäkelä.
During a query execution some sorting and grouping operations
on strings may be involved. System variable max_sort_length defines
the maximum number of bytes to use when comparing strings during
sorting/grouping. Thus, the comparable parts of strings may be less
than their actual size, so the results of the query may be not
sorted/grouped properly.
To indicate that some comparisons were done on a truncated lengths,
a new warning has been introduced with this commit.
If semi-sync is switched off then on while a transaction is
in-between binlogging and waiting for an ACK, the semi-sync state of
the transaction is removed, leading to a debug assertion that
indicates the transaction tried to wait, but cannot receive an ACK
signal. More specifically, when semi-sync is switched off, the
Active_tranx list is cleared (where a transaction adds an entry to
this list during binlogging), and each entry in this list saves the
thread which will wait for an ACK, and the thread has the COND
variable to signal to wake itself. So if the entry is lost, the
Ack_receiver thread won’t be able to find the thread to wake up when
an ACK comes in
The fix is to ensure that the entry exists before awaiting the ACK,
and if there is no entry, skip the wait. In debug builds, an
informative message is written explaining that the transaction is
skipping its wait. Additional debug-build only logic is added to
ensure that the cause of the missing entry is due to semi-sync being
turned off and on
Reviewed By:
============
Kristian Nielsen <knielsen@knielsen-hq.org>
The problem was that when using clang + asan, we do not get a correct value
for the thread stack as some local variables are not allocated at the
normal stack.
It looks like that for example clang 18.1.3, when compiling with
-O2 -fsanitize=addressan it puts local variables and things allocated by
alloca() in other areas than on the stack.
The following code shows the issue
Thread 6 "mariadbd" hit Breakpoint 3, do_handle_one_connection
(connect=0x5080000027b8,
put_in_cache=<optimized out>) at sql/sql_connect.cc:1399
THD *thd;
1399 thd->thread_stack= (char*) &thd;
(gdb) p &thd
(THD **) 0x7fffedee7060
(gdb) p $sp
(void *) 0x7fffef4e7bc0
The address of thd is 24M away from the stack pointer
(gdb) info reg
...
rsp 0x7fffef4e7bc0 0x7fffef4e7bc0
...
r13 0x7fffedee7060 140737185214560
r13 is pointing to the address of the thd. Probably some kind of
"local stack" used by the sanitizer
I have verified this with gdb on a recursive call that calls alloca()
in a loop. In this case all objects was stored in a local heap,
not on the stack.
To solve this issue in a portable way, I have added two functions:
my_get_stack_pointer() returns the address of the current stack pointer.
The code is using asm instructions for intel 32/64 bit, powerpc,
arm 32/64 bit and sparc 32/64 bit.
Supported compilers are gcc, clang and MSVC.
For MSVC 64 bit we are using _AddressOfReturnAddress()
As a fallback for other compilers/arch we use the address of a local
variable.
my_get_stack_bounds() that will return the address of the base stack
and stack size using pthread_attr_getstack() or NtCurrentTed() with
fallback to using the address of a local variable and user provided
stack size.
Server changes are:
- Moving setting of thread_stack to THD::store_globals() using
my_get_stack_bounds().
- Removing setting of thd->thread_stack, except in functions that
allocates a lot on the stack before calling store_globals(). When
using estimates for stack start, we reduce stack_size with
MY_STACK_SAFE_MARGIN (8192) to take into account the stack used
before calling store_globals().
I also added a unittest, stack_allocation-t, to verify the new code.
Reviewed-by: Sergei Golubchik <serg@mariadb.org>
Implement variable legacy_xa_rollback_at_disconnect to support
backwards compatibility for applications that rely on the pre-10.5
behavior for connection disconnect, which is to rollback the
transaction (in violation of the XA specification).
Signed-off-by: Kristian Nielsen <knielsen@knielsen-hq.org>
Fixed by checking handler_stats if it's active instead of
thd->variables.log_slow_verbosity & LOG_SLOW_VERBOSITY_ENGINE.
Reviewed-by: Sergei Petrunia <sergey@mariadb.com>
If a slave replicating an event has waited for more than
@@slave_abort_blocking_timeout for a conflicting metadata lock held by a
non-replication thread, the blocking query is killed to allow replication to
proceed and not be blocked indefinitely by a user query.
Reviewed-by: Monty <monty@mariadb.org>
Signed-off-by: Kristian Nielsen <knielsen@knielsen-hq.org>
