The table opening process now works the following way:
- Create common TABLE_SHARE object
- Read the .frm file and unpack it into the TABLE_SHARE object
- Create a TABLE object based on the information in the TABLE_SHARE
object and open a handler to the table object
Other noteworthy changes:
- In TABLE_SHARE the most common strings are now LEX_STRING's
- Better error message when table is not found
- Variable table_cache is now renamed 'table_open_cache'
- New variable 'table_definition_cache' that is the number of table defintions that will be cached
- strxnmov() calls are now fixed to avoid overflows
- strxnmov() will now always add one end \0 to result
- engine objects are now created with a TABLE_SHARE object instead of a TABLE object.
- After creating a field object one must call field->init(table) before using it
- For a busy system this change will give you:
- Less memory usage for table object
- Faster opening of tables (if it's has been in use or is in table definition cache)
- Allow you to cache many table definitions objects
- Faster drop of table
Not fixed in 4.1 as not critical. Also I'm correcting error checking of multi-UPDATE/DELETE
when it comes to binlogging, to make it consistent with when we rollback the statement.
"Interleaved SPs execution is now binlogged properly, "SELECT spfunc()" is binlogged too.
The known remaining issue is binlogging/replication of "a routine is deleted while it is executed" scenario.
"Process NATURAL and USING joins according to SQL:2003".
* Some of the main problems fixed by the patch:
- in "select *" queries the * expanded correctly according to
ANSI for arbitrary natural/using joins
- natural/using joins are correctly transformed into JOIN ... ON
for any number/nesting of the joins.
- column references are correctly resolved against natural joins
of any nesting and combined with arbitrary other joins.
* This patch also contains a fix for name resolution of items
inside the ON condition of JOIN ... ON - in this case items must
be resolved only against the JOIN operands. To support such
'local' name resolution, the patch introduces a stack of
name resolution contexts used at parse time.
NOTICE:
- This patch is not complete in the sense that
- there are 2 test cases that still do not pass -
one in join.test, one in select.test. Both are marked
with a comment "TODO: WL#2486".
- it does not include a new test specific for the task
cause crash on update".
Let us update "thd" pointer in LEX, all its units and in LEX::result before
executing statement in trigger body, since triggers are associated with TABLE
object and because of this can be used in different threads.
"the server side preparedStatement error for LIMIT placeholder",
which moves all uses of LIMIT clause from PREPARE to OPTIMIZE
and later steps.
After-review fixes.
databases" and basic handling of errors which happen in triggers.
(The bug itself was fixed by several previous patches).
Fixed bug in multi-delete which were exposed by these tests.
#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.
