crash if referencing a table" and several other related bugs.
Fix for bug #11834 "Re-execution of prepared statement with dropped function
crashes server." which was spotted during work on previous bugs.
Also couple of nice cleanups:
- Replaced two separate hashes for stored routines used by statement with one.
- Now instead of doing one pass through all routines used in statement for
caching them and then doing another pass for adding their tables to table
list, we do only one pass during which do both things.
We should not allow explicit or implicit transaction commits inside
of stored functions or triggers (so in autocommit mode we should not
do commits after execution of sub-statement).
Also since we don't support nested statement transactions in 5.0,
we shouldn't commit or rollback stmt transactions while we are inside
stored functions or triggers. This should be fixed in later (>=5.1)
releases.
#5860 "Multi-table UPDATE does not activate update triggers"
#6812 "Triggers are not activated for INSERT ... SELECT"
#8755 "Trigger is not activated by LOAD DATA".
This patch also implements proper handling of triggers for special forms
of insert like REPLACE or INSERT ... ON DUPLICATE KEY UPDATE.
Also now we don't call after trigger in case when we have failed to
inserted/update or delete row. Trigger failure should stop statement
execution.
I have not properly tested handling of errors which happen inside of
triggers in this patch, since it is simplier to do this once we will be
able to access tables from triggers.
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.
out of order". (final version)
Now instead of binding Item_trigger_field to TABLE objects during
trigger definition parsing at table open, we perform pass through
special list of all such objects in trigger. This allows easily check
all references to fields in old/new version of row in trigger during
execution of CREATE TRIGGER statement (this is more courtesy for users
since we can't check everything anyway).
We also report that such reference is bad by returning error from
Item_trigger_field::fix_fields() method (instead of setup_field())
This means that if trigger is broken we will bark during trigger
execution instead of trigger definition parsing at table open.
(i.e. now we allow to open tables with broken triggers).
If we have DELETE with always true WHERE clause we should not use
optimized delete_all_rows() method for tables with DELETE triggers,
because in this case we will lose side-effect of deletion.
Mostly needed for Monty for him getting notion what needed for triggers
from new .FRM format.
Things to be done:
- Right placement of trigger's invocations
- Right handling of errors in triggers (including transaction rollback)
- Support for priviliges
- Right handling of DROP/RENAME table (hope that it will be handled automatically
with merging of .TRG into .FRM file)
- Saving/restoring some information critical for trigger creation and replication
with their definitions (e.g. sql_mode, creator, ...)
- Replication
Already has some known bugs so probably not for general review.
