Remove mysql_lock_have_duplicate(), since now we always
have TABLE_LIST objects for MyISAMMRG children
in lex->query_tables and keep it till the end of the
statement (sub-statement).
This bug is a consequence of WL#5349, as the
default storage engine was changed.
The fix was to explicitly add an ENGINE
clause to a CREATE TABLE statement, to
ensure that we test case preservement on
MyISAM.
The problem was that if a query accessing a view was blocked due to
conflicting locks on tables in the view definition, it would be possible
for a different connection to alter the view definition before the view
query completed. When the view query later resumed, it used the old view
definition. This meant that if the view query was later repeated inside
the same transaction, the two executions of the query would give different
results, thus breaking repeatable read. (The first query used the old
view definition, the second used the new view definition).
This bug is no longer repeatable with the recent changes to the metadata
locking subsystem (revno: 3040). The view query will no longer back-off
and release the lock on the view definiton. Instead it will wait for
the conflicting lock(s) to go away while keeping the view definition lock.
This means that it is no longer possible for a concurrent connection to
alter the view definition. Instead, any such attempt will be blocked.
In the case from the bug report where the same view query was executed
twice inside the same transaction, any ALTER VIEW from other connections
will now be blocked until the transaction has completed (or aborted).
The view queries will therefore use the same view definition and we will
have repeatable read.
Test case added to innodb_mysql_lock.test.
This patch contains no code changes.
Bug#47633 - assert in ha_myisammrg::info during OPTIMIZE
The server crashed on an attempt to optimize a MERGE table with
non-existent child table.
mysql_admin_table() relied on the table to be successfully open
if a table object had been allocated.
Changed code to check return value of the open function before
calling a handler:: function on it.
DML flow and SAVEPOINT
The problem was that replication could break if a transaction involving
both transactional and non-transactional tables was rolled back to a
savepoint. It broke if a concurrent connection tried to drop a
transactional table which was locked after the savepoint was set.
This DROP TABLE completed when ROLLBACK TO SAVEPOINT was executed as the
lock on the table was dropped by the transaction. When the slave later
tried to apply the binlog, it would fail as the table would already
have been dropped.
The reason for the problem is that transactions involving both
transactional and non-transactional tables are written fully to the
binlog during ROLLBACK TO SAVEPOINT. At the same time, metadata locks
acquired after a savepoint, were released during ROLLBACK TO SAVEPOINT.
This allowed a second connection to drop a table only used between
SAVEPOINT and ROLLBACK TO SAVEPOINT. Which caused the transaction binlog
to refer to a non-existing table when it was written during ROLLBACK
TO SAVEPOINT.
This patch fixes the problem by not releasing metadata locks when
ROLLBACK TO SAVEPOINT is executed if binlogging is enabled.
The assert was triggered if a connection executing TRUNCATE
on a InnoDB table was killed during open_tables.
This bug was fixed in the scope of Bug #45643
"InnoDB does not support replication of TRUNCATE TABLE".
This patch adds test coverage to innodb_mysql_sync.test.
Accidental change in compile-time definitions for FreeBSD
Revert the accidental setting of "HAVE_BROKEN_REALPATH"
on current versions of FreeBSD,
do it for both autotools ("configure.in")
and cmake ("cmake/os/FreeBSD.cmake").
------------------------------------------------------------
revno: 3672
committer: lars-erik.bjork@sun.com
branch nick: 48067-mysql-6.0-codebase-bugfixing
timestamp: Mon 2009-10-26 13:51:43 +0100
message:
This is a patch for bug#48067
"A temp table with the same name as an existing table, makes drop
database fail"
When dropping the database, mysql_rm_known_files() reads the contents
of the database directory, and creates a TABLE_LIST object, for each
.frm file encountered. Temporary tables, however, are not associated
with any .frm file.
The list of tables to drop are passed to mysql_rm_table_part2().
This method prefers temporary tables over regular tables, so if
there is a temporary table with the same name as a regular, the
temporary is removed, leaving the regular table intact.
Regular tables are only deleted if there are no temporary tables
with the same name.
This fix ensures, that for all TABLE_LIST objects that are created
by mysql_rm_known_files(), 'open_type' is set to 'OT_BASE_ONLY', to
indicate that this is a regular table. In all cases in
mysql_rm_table_part2() where we prefer a temporary table to a
non-temporary table, we chek if 'open_type' equals 'OT_BASE_ONLY'.
use limit efficiently
Bug #36569: UPDATE ... WHERE ... ORDER BY... always does a
filesort even if not required
Also two bugs reported after QA review (before the commit
of bugs above to public trees, no documentation needed):
Bug #53737: Performance regressions after applying patch
for bug 36569
Bug #53742: UPDATEs have no effect after applying patch
for bug 36569
Execution of single-table UPDATE and DELETE statements did not use the
same optimizer as was used in the compilation of SELECT statements.
Instead, it had an optimizer of its own that did not take into account
that you can omit sorting by retrieving rows using an index.
Extra optimization has been added: when applicable, single-table
UPDATE/DELETE statements use an existing index instead of filesort. A
corresponding SELECT query would do the former.
Also handling of the DESC ordering expression has been added when
reverse index scan is applicable.
From now on most single table UPDATE and DELETE statements show the
same disk access patterns as the corresponding SELECT query. We verify
this by comparing the result of SHOW STATUS LIKE 'Sort%
Currently the get_index_for_order function
a) checks quick select index (if any) for compatibility with the
ORDER expression list or
b) chooses the cheapest available compatible index, but only if
the index scan is cheaper than filesort.
Second way is implemented by the new test_if_cheaper_ordering
function (extracted part the test_if_skip_sort_order()).
subsystem. Fix a number of caveates that the previous
implementation suffered from, including unprotected
access to shared data and lax resource accounting
(share->ref_count) that could lead to deadlocks.
The new implementation still suffers from a number
of potential deadlocks in some edge cases, and this is
still not enabled by default. Especially since performance
testing has shown that it gives only marginable (not even
exceeding measuring accuracy) improvements.
@todo:
- Remove calls to close_cached_tables() with REFRESH_FAST,
and have_lock, because they break the MDL cache.
- rework FLUSH TABLES <list> to not use close_cached_tables()
- make sure that whenever we set TABLE_SHARE::version to
0 we free MDL cache references to it.
The default storage engine is changed from MyISAM to
InnoDB, in all builds except for the embedded server.
In addition, the following system variables are
changed:
* innodb_file_per_table is enabled
* innodb_strict_mode is enabled
* innodb_file_format_name_update is changed
to 'Barracuda'
The test suite is changed so that tests that do not
explicitly include the have_innodb.inc are run with
--default-storage-engine=MyISAM. This is to ease the
transition, so that most regression tests are run
with the same engine as before.
Some tests are disabled for the embedded server
regression test, as the output of certain statements
will be different that for the regular server
(i.e SELECT @@default_storage_engine). This is to
ease transition.
line exceeds the limit
The number and/or names of our files for the main test suite
(contents of "mysql-test/t/") now exceeds the command line
length limit on AIX.
Solve the problem by using separate "cp" commands for the
various file name extensions.
