and some SP-related cleanups.
- We don't have separate stage for calculation of list of tables
to be prelocked and doing implicit LOCK/UNLOCK any more.
Instead we calculate this list at open_tables() and do implicit
LOCK in lock_tables() (and UNLOCK in close_thread_tables()).
Also now we support cases when same table (with same alias) is
used several times in the same query in SP.
- Cleaned up execution of SP. Moved all common code which handles
LEX and does preparations before statement execution or complex
expression evaluation to auxilary sp_lex_keeper class. Now
all statements in SP (and corresponding instructions) that
evaluate expression which can contain subquery have their
own LEX.
and bug#8849 "problem with insert statement with table alias's":
make equality propagation work in stored procedures and prepared
statements.
Equality propagation can change AND/OR structure of ON expressions,
so the fix is to provide each execution of PS/SP with it's own
copy of AND/OR tree. We have been doing that already for WHERE clauses,
now ON clauses are also copied.
Collect all tables and SPs refered by a statement, and open all tables
with an implicit LOCK TABLES. Do find things refered by triggers and views,
we open them first (and then repeat this until nothing new is found), before
doing the actual lock tables.
The bug was that if you have two TL_WRITE_DELAYED at the same time,
mi_lock_databases() could be done in the wrong order and we could write the wrong header to the MyISAM index file.
This fixed a bug in prepared statements when used with outher joins
Fixed a bug in SUM(DISTINCT) when used with prepared statements.
Some safety fixes in test scripts to ensure that previous test failures shouldn't affect other tests
tables requires privileges for them if some table or column level grants
present" (with after-review fixes).
We should set SELECT_ACL for implicitly opened tables in
my_tz_check_n_skip_implicit_tables() to be able to bypass privilege
checking in check_grant(). Also we should exclude those tables from
privilege checking in multi-update.
In server we assume that datetime values stored in MYSQL_TIME struct
are normalized (and year is not greater than 9999), so we should
perform range checks in all places then we convert something to
MYSQL_TIME.
Added push_back(void *, MEM_ROOT *) to make some list-handling code easier that needs to be allocated in a different mem-root
(Before one had to change thd->mem_root ; push_back(); restore mem_root.
Now thd->mem_root is a pointer to thd->main_mem_root and THR_MALLOC is a pointer to thd->mem_root.
This gives us the following benefits:
- Allow us to easily detect if arena has already been swapped before (this fixes a bug in setup_conds() where arena was swaped twice in some cases)
- Faster swaps of arenas (as we don't have to copy the whole MEM_ROOT)
- We don't anymore have to call my_pthread_setspecific_ptr(THR_MALLOC,...) to change where memory is alloced. Now it's enough to set thd->mem_root
and blank after function name".
Crop fruits of copy-paste programming: pre-caching of stored functions
wasn't performed for prepared statements just because implementation
of prepared statements is done as an add-on to the main execution flow,
and the preload was originally implemented for main execution branch
only (mysql_execute_command).
