The failure was caused by executing a CREATE-SELECT statement that creates a
table in another database than the current one. In row-based logging, the
CREATE statement was written to the binary log without the database, hence
creating the table in the wrong database, causing the following inserts to
fail since the table didn't exist in the given database.
Fixed the bug by adding a parameter to store_create_info() that will make
the function print the database name before the table name and used that
in the calls that write the CREATE statement to the binary log. The database
name is only printed if it is different than the currently selected database.
The output of SHOW CREATE TABLE has not changed and is still printed without
the database name.
"Trigger fired multiple times leads to gaps in auto_increment sequence".
The bug was that if a trigger fired multiple times inside a top
statement (for example top-statement is a multi-row INSERT,
and trigger is ON INSERT), and that trigger inserted into an auto_increment
column, then gaps could be observed in the auto_increment sequence,
even if there were no other users of the database (no concurrency).
It was wrong usage of THD::auto_inc_intervals_in_cur_stmt_for_binlog.
Note that the fix changes "class handler", I'll tell the Storage Engine API team.
This patch contains fixes for two problems:
1. As originally reported, the server crashed on Mac OS X when trying to access
an EXAMPLE table after the EXAMPLE plugin was installed.
It turned out that the dynamically loaded EXAMPLE plugin called the
function hash_earch() from a Mac OS X system library, instead of
hash_earch() from MySQL's mysys library. Makefile.am in storage/example
does not include libmysys. So the Mac OS X linker arranged the hash_search()
function to be linked to the system library when the shared object is
loaded.
One possible solution would be to include libmysys into the linkage of
dynamic plugins. But then we must have a libmysys.so, which must be
used by the server too. This could have a minimal performance impact,
but foremost the change seems to bee too risky at the current state of
MySQL 5.1.
The selected solution is to rename MySQL's hash_search() to my_hash_search()
like it has been done before with hash_insert() and hash_reset().
Since this is the third time, we need to rename a hash_*() function,
I did renamed all hash_*() functions to my_hash_*().
To avoid changing a zillion calls to these functions, and announcing
this to hundreds of developers, I added defines that map the old names
to the new names.
This change is in hash.h and hash.c.
2. The other problem was improper implementation of the handlerton-to-plugin
mapping. We use a fixed-size array to hold a plugin reference for each
handlerton. On every install of a handler plugin, we allocated a new slot
of the array. On uninstall we did not free it. After some uninstall/install
cycles the array overflowed. We did not check for overflow.
One fix is to check for overflow to stop the crashes.
Another fix is to free the array slot at uninstall and search for a free slot
at plugin install.
This change is in handler.cc.
SET col
When reporting a duplicate key error the server was making incorrect assumptions
on what the state of the value string to include in the error is.
Fixed by accessing the data in this string in a "safe" way (without relying on it
having a terminating 0).
Detected by code analysis and fixed a similar problem in reporting the foreign key
duplicate errors.
partition is corrupt
The main problem was that ALTER TABLE t ANALYZE/CHECK/OPTIMIZE/REPAIR
PARTITION took another code path (over mysql_alter_table instead of
mysql_admin_table) which differs in two ways:
1) alter table opens the tables in a different way than admin tables do
resulting in returning with error before it tried the command
2) alter table does not start to send any diagnostic rows to the client
which the lower admin functions continue to use -> resulting in
assertion crash
The fix:
Remapped ALTER TABLE t ANALYZE/CHECK/OPTIMIZE/REPAIR PARTITION to use
the same code path as ANALYZE/CHECK/OPTIMIZE/REPAIR TABLE t.
Adding check in mysql_admin_table to setup the partition list for
which partitions that should be used.
Partitioned tables will still not work with
REPAIR TABLE/PARTITION USE_FRM, since that requires moving partitions
to tables, REPAIR TABLE t USE_FRM, and check that the data still
fulfills the partitioning function and then move the table back to
being a partition.
NOTE: I have removed the following functions from the handler
interface:
analyze_partitions, check_partitions, optimize_partitions,
repair_partitions
Since they are not longer needed.
THIS ALTERS THE STORAGE ENGINE API
Problem was that ha_partition had HA_FILE_BASED flag set
(since it uses a .par file), but after open it uses the first partitions
flags, which results in different case handling for create and for
open.
Solution was to change the underlying partition name so it was consistent.
(Only happens when lower_case_table_names = 2, i.e. Mac OS X and storage
engines without HA_FILE_BASED, like InnoDB and Memory.)
(Recommit after adding rename of check_lowercase_names to
get_canonical_filename, and moved it from handler.h to mysql_priv.h)
NOTE: if a mixed case name for a partitioned table was created when
lower_case_table_name = 2 it should be renamed or dropped before using
the updated version (See bug#37402 for more info)
The REPAIR TABLE ... USE_FRM query silently corrupts data of tables
with old .FRM file version.
The mysql_upgrade client program or the REPAIR TABLE query (without
the USE_FRM clause) can't prevent this trouble, because in the
common case they don't upgrade .FRM file to compatible structure.
1. Evaluation of the REPAIR TABLE ... USE_FRM query has been
modified to reject such tables with the message:
"Failed repairing incompatible .FRM file".
2. REPAIR TABLE query (without USE_FRM clause) evaluation has been
modified to upgrade .FRM files to current version.
3. CHECK TABLE ... FOR UPGRADE query evaluation has been modified
to return error status when .FRM file has incompatible version.
4. mysql_upgrade and mysqlcheck client programs call CHECK TABLE
FOR UPGRADE and REPAIR TABLE queries, so their behaviors have
been changed too to upgrade .FRM files with incompatible
version numbers.
a SELECT doesn't cause ROLLBACK of statem".
The idea of the fix is to ensure that we always commit the current
statement at the end of dispatch_command(). In order to not issue
redundant disc syncs, an optimization of the two-phase commit
protocol is implemented to bypass the two phase commit if
the transaction is read-only.
Replacing a template function with a normal static function.
The template parameter, which previously was the class to
find a binlogging function in, is now passed as a pointer to
the actual binlogging function instead.
The patch requires change of indention, but that is submitted
as a separate patch.
The bug was that handler::clone/handler::ha_open() call caused allocation of
cloned_copy->ref on the handler->table->mem_root. The allocated memory could not
be reclaimed until the table is flushed, so it was possible to exhaust memory by
repeatedly running index_merge queries without doing table flushes.
The fix:
- make handler::clone() allocate new_handler->ref on the passed mem_root
- make handler::ha_open() not allocate this->ref if it has already been allocated
There is no testcase as it is not possible to check small leaks from testsuite.
called from a SELECT doesn't cause ROLLBACK of state"
Make private all class handler methods (PSEA API) that may modify
data. Introduce and deploy public ha_* wrappers for these methods in
all sql/.
This necessary to keep track of all data modifications in sql/,
which is in turn necessary to be able to optimize two-phase
commit of those transactions that do not modify data.
corrupts a MERGE table
Bug 26867 - LOCK TABLES + REPAIR + merge table result in
memory/cpu hogging
Bug 26377 - Deadlock with MERGE and FLUSH TABLE
Bug 25038 - Waiting TRUNCATE
Bug 25700 - merge base tables get corrupted by
optimize/analyze/repair table
Bug 30275 - Merge tables: flush tables or unlock tables
causes server to crash
Bug 19627 - temporary merge table locking
Bug 27660 - Falcon: merge table possible
Bug 30273 - merge tables: Can't lock file (errno: 155)
The problems were:
Bug 26379 - Combination of FLUSH TABLE and REPAIR TABLE
corrupts a MERGE table
1. A thread trying to lock a MERGE table performs busy waiting while
REPAIR TABLE or a similar table administration task is ongoing on
one or more of its MyISAM tables.
2. A thread trying to lock a MERGE table performs busy waiting until all
threads that did REPAIR TABLE or similar table administration tasks
on one or more of its MyISAM tables in LOCK TABLES segments do UNLOCK
TABLES. The difference against problem #1 is that the busy waiting
takes place *after* the administration task. It is terminated by
UNLOCK TABLES only.
3. Two FLUSH TABLES within a LOCK TABLES segment can invalidate the
lock. This does *not* require a MERGE table. The first FLUSH TABLES
can be replaced by any statement that requires other threads to
reopen the table. In 5.0 and 5.1 a single FLUSH TABLES can provoke
the problem.
Bug 26867 - LOCK TABLES + REPAIR + merge table result in
memory/cpu hogging
Trying DML on a MERGE table, which has a child locked and
repaired by another thread, made an infinite loop in the server.
Bug 26377 - Deadlock with MERGE and FLUSH TABLE
Locking a MERGE table and its children in parent-child order
and flushing the child deadlocked the server.
Bug 25038 - Waiting TRUNCATE
Truncating a MERGE child, while the MERGE table was in use,
let the truncate fail instead of waiting for the table to
become free.
Bug 25700 - merge base tables get corrupted by
optimize/analyze/repair table
Repairing a child of an open MERGE table corrupted the child.
It was necessary to FLUSH the child first.
Bug 30275 - Merge tables: flush tables or unlock tables
causes server to crash
Flushing and optimizing locked MERGE children crashed the server.
Bug 19627 - temporary merge table locking
Use of a temporary MERGE table with non-temporary children
could corrupt the children.
Temporary tables are never locked. So we do now prohibit
non-temporary chidlren of a temporary MERGE table.
Bug 27660 - Falcon: merge table possible
It was possible to create a MERGE table with non-MyISAM children.
Bug 30273 - merge tables: Can't lock file (errno: 155)
This was a Windows-only bug. Table administration statements
sometimes failed with "Can't lock file (errno: 155)".
These bugs are fixed by a new implementation of MERGE table open.
When opening a MERGE table in open_tables() we do now add the
child tables to the list of tables to be opened by open_tables()
(the "query_list"). The children are not opened in the handler at
this stage.
After opening the parent, open_tables() opens each child from the
now extended query_list. When the last child is opened, we remove
the children from the query_list again and attach the children to
the parent. This behaves similar to the old open. However it does
not open the MyISAM tables directly, but grabs them from the already
open children.
When closing a MERGE table in close_thread_table() we detach the
children only. Closing of the children is done implicitly because
they are in thd->open_tables.
For more detail see the comment at the top of ha_myisammrg.cc.
Changed from open_ltable() to open_and_lock_tables() in all places
that can be relevant for MERGE tables. The latter can handle tables
added to the list on the fly. When open_ltable() was used in a loop
over a list of tables, the list must be temporarily terminated
after every table for open_and_lock_tables().
table_list->required_type is set to FRMTYPE_TABLE to avoid open of
special tables. Handling of derived tables is suppressed.
These details are handled by the new function
open_n_lock_single_table(), which has nearly the same signature as
open_ltable() and can replace it in most cases.
In reopen_tables() some of the tables open by a thread can be
closed and reopened. When a MERGE child is affected, the parent
must be closed and reopened too. Closing of the parent is forced
before the first child is closed. Reopen happens in the order of
thd->open_tables. MERGE parents do not attach their children
automatically at open. This is done after all tables are reopened.
So all children are open when attaching them.
Special lock handling like mysql_lock_abort() or mysql_lock_remove()
needs to be suppressed for MERGE children or forwarded to the parent.
This depends on the situation. In loops over all open tables one
suppresses child lock handling. When a single table is touched,
forwarding is done.
Behavioral changes:
===================
This patch changes the behavior of temporary MERGE tables.
Temporary MERGE must have temporary children.
The old behavior was wrong. A temporary table is not locked. Hence
even non-temporary children were not locked. See
Bug 19627 - temporary merge table locking.
You cannot change the union list of a non-temporary MERGE table
when LOCK TABLES is in effect. The following does *not* work:
CREATE TABLE m1 ... ENGINE=MRG_MYISAM ...;
LOCK TABLES t1 WRITE, t2 WRITE, m1 WRITE;
ALTER TABLE m1 ... UNION=(t1,t2) ...;
However, you can do this with a temporary MERGE table.
You cannot create a MERGE table with CREATE ... SELECT, neither
as a temporary MERGE table, nor as a non-temporary MERGE table.
CREATE TABLE m1 ... ENGINE=MRG_MYISAM ... SELECT ...;
Gives error message: table is not BASE TABLE.
the wrong buffer
handler::index_next_same() did not take into account that the
internally called function key_cmp_if_same() uses the fixed
buffer table->record[0] for key comparison instead of the
buffer provided by the caller of handler::index_next_same().
Added code to temporarily redirect table->record[0] and the fields
used for the key to the record buffer provided by the caller of
handler::index_next_same().
The test case is in partition.test already.
and convert it to a warning instead of direct manipulation with the
thread error stack.
Fix a bug in handler::print_erorr when a garbled message was
printed for HA_ERR_NO_SUCH_TABLE.
This is a pre-requisite patch for the fix for Bug#12713 Error in a stored
function called from a SELECT doesn't cause ROLLBACK of statem
