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
into mysql.com:/home/mysql_src/mysql-5.1-merge-of-5.0
(2nd try; Pekka kindly accepted to fix storage/ndb/src/kernel/blocks/dbtup/DbtupRoutines.cpp
and storage/ndb/src/kernel/vm/SimulatedBlock.cpp after I push).
Version for 5.0.
It fixes three problems:
1. The cause of the bug was that we did not check the table version for
the HANDLER ... READ commands. We did not notice when a table was
replaced by a new one. This can happen during ALTER TABLE, REPAIR
TABLE, and OPTIMIZE TABLE (there might be more cases). I call the fix
for this problem "the primary bug fix".
2. mysql_ha_flush() was not always called with a locked LOCK_open.
Though the function comment clearly said it must.
I changed the code so that the locking is done when required. I call
the fix for this problem "the secondary fix".
3. In 5.0 (not in 4.1 or 4.0) DROP TABLE had a possible deadlock flaw in
concur with FLUSH TABLES WITH READ LOCK. I call the fix for this
problem "the 5.0 addendum fix".
large table gives server crash": make sure that when a MyISAM temporary
table is created for a cursor, it's created in its memory root,
not the memory root of the current query.
droping trigger on InnoDB table".
Deadlock occured in cases when we were trying to create two triggers for
the same InnoDB table concurrently and both threads were able to reach
close_cached_table() simultaneously. Bugfix implements new approach to
table locking and table cache invalidation during creation/dropping
of trigger.
No testcase is supplied since bug was repeatable only under high concurrency.
- CHAR() now returns binary string as default
- CHAR(X*65536+Y*256+Z) is now equal to CHAR(X,Y,Z) independent of the character set for CHAR()
- Test for both ETIMEDOUT and ETIME from pthread_cond_timedwait()
(Some old systems returns ETIME and it's safer to test for both values
than to try to write a wrapper for each old system)
- Fixed new introduced bug in NOT BETWEEN X and X
- Ensure we call commit_by_xid or rollback_by_xid for all engines, even if one engine has failed
- Use octet2hex() for all conversion of string to hex
- Simplify and optimize code
The problem was then when a column reference was resolved to a view column, the new Item
created for this column contained the name of the view, and not the view alias.
"SELECT ... FOR UPDATE executed as consistent read inside LOCK TABLES"
Do not discard lock_type information as handler::start_stmt() may require knowledge.
(fixed by Antony)
Fixed bug #13411.
Fixed name resolution for non-qualified reference to a view column
in the HAVING clause.
view.result, view.test:
Added a test case for bug #13411.
Fixed problems in test suite where some test failed
Fixed access to not initialized memory in federated
Fixed access to not initialized memory when using BIT fields in internal temporary tables
The problem was in the way table references are pre-filtered when
resolving a qualified field. When resolving qualified table references
we search recursively in the operands of the join. If there is
natural/using join with a merge view, the first call to find_field_in_table_ref
makes a recursive call to itself with the view as the new table reference
to search for the column. However the view has both nested_join and
join_columns != NULL so it skipped the test whether the view name matches
the field qualifier. As a result the field was found in the view since the
view already has a field with the same name. Thus the field was incorrectly
resolved as the view field.
This bug occurs when some trigger for table used by DML statement is created
or changed while statement was waiting in lock_tables(). In this situation
prelocking set which we have calculated becames invalid which can easily lead
to errors and even in some cases to crashes.
With proposed patch we no longer silently reopen tables in lock_tables(),
instead caller of lock_tables() becomes responsible for reopening tables and
recalculation of prelocking set.
Solution for 5.0.
Changed calls to open_table(). Requested to ignore
flush at places where the command did already lock tables.
This could happen in CREATE ... SELECT and ALTER TABLE.
No test case. The bug can only be triggered by true concurrency.
The stress test suite provides a test case for this.
