Problem: sha2() reported its result as BINARY
Fix:
- Inheriting Item_func_sha2 from Item_str_ascii_func
- Setting max_length via fix_length_and_charset()
instead of direct assignment.
- Adding tests
Problem: Item_copy did not set "fixed", which resulted in DBUG_ASSERT in some cases.
Fix: adding initialization of the "fixed" member
Adding tests:
mysql-test/include/ctype_numconv.inc
mysql-test/r/ctype_binary.result
mysql-test/r/ctype_cp1251.result
mysql-test/r/ctype_latin1.result
mysql-test/r/ctype_ucs.result
Adding initialization of the "fixed" member:
sql/item.h
value and NO_ZERO_DATE
The problem was that a older version of the error path for a
failed admin statement relied upon a few error conditions being
met in order to access a table handler, the first one being that
the table object pointer was not NULL. Probably due to chance,
in all cases a table object was closed but the reference wasn't
reset, the other conditions didn't evaluate to true. With the
addition of a new check on the error path, the handler started
being dereferenced whenever it was not reset to NULL, causing
problems for code paths which closed the table but didn't reset
the reference.
The solution is to reset the reference whenever a admin statement
fails and the tables are closed.
large-pages option is broken) from next-mr to trunk-bugfixing.
Original revision:
------------------------------------------------------------
revision-id: vvaintroub@mysql.com-20100416134524-y4v27j90p5xvblmy
parent: luis.soares@sun.com-20100416000700-n267ynu77visx31t
committer: Vladislav Vaintroub <vvaintroub@mysql.com>
branch nick: mysql-next-mr-bugfixing
timestamp: Fri 2010-04-16 15:45:24 +0200
message:
Bug #52716 Large files support is disabled, large-pages option is broken.
Correct typo: large pages option was tied to wrong variable opt_large_files,
instead of opt_large_pages.
------------------------------------------------------------
BUG#54872 MBR: replication failure caused by using tmp table inside transaction
Changed criteria to classify a statement as unsafe in order to reduce the
number of spurious warnings. So a statement is classified as unsafe when
there is on-going transaction at any point of the execution if:
1. The mixed statement is about to update a transactional table and
a non-transactional table.
2. The mixed statement is about to update a temporary transactional
table and a non-transactional table.
3. The mixed statement is about to update a transactional table and
read from a non-transactional table.
4. The mixed statement is about to update a temporary transactional
table and read from a non-transactional table.
5. The mixed statement is about to update a non-transactional table
and read from a transactional table when the isolation level is
lower than repeatable read.
After updating a transactional table if:
6. The mixed statement is about to update a non-transactional table
and read from a temporary transactional table.
7. The mixed statement is about to update a non-transactional table
and read from a temporary transactional table.
8. The mixed statement is about to update a non-transactionala table
and read from a temporary non-transactional table.
9. The mixed statement is about to update a temporary non-transactional
table and update a non-transactional table.
10. The mixed statement is about to update a temporary non-transactional
table and read from a non-transactional table.
11. A statement is about to update a non-transactional table and the
option variables.binlog_direct_non_trans_update is OFF.
The reason for this is that locks acquired may not protected a concurrent
transaction of interfering in the current execution and by consequence in
the result. So the patch reduced the number of spurious unsafe warnings.
Besides we fixed a regression caused by BUG#51894, which makes temporary
tables to go into the trx-cache if there is an on-going transaction. In
MIXED mode, the patch for BUG#51894 ignores that the trx-cache may have
updates to temporary non-transactional tables that must be written to the
binary log while rolling back the transaction.
So we fix this problem by writing the content of the trx-cache to the
binary log while rolling back a transaction if a non-transactional
temporary table was updated and the binary logging format is MIXED.
mysqld-debug.exe in 5.5.3 on windows
Fix:
- Do not rename PDB, install mysqld.pdb matching
mysqld-debug.exe into bin\debug subdirectory
- Stack tracing code will now additionally look in
debug subdirectory of the application directory
for debug symbols.
- Small cleanup in stacktracing code: link with
dbghelp rather than load functions dynamically
at runtime, since dbghelp.dll is always present.
- Install debug binaries with WiX
switching binlog format to ROW
BUG 52616 fixed the case which the user would switch from STMT to
ROW binlog format, but the server would silently ignore it. After
that fix thd->is_current_stmt_binlog_format_row() reports correct
value at logging time and events are logged in ROW (as expected)
instead of STMT as they were previously and wrongly logged.
However, the fix was only partially complete, because on
disconnect, at THD cleanup, the implicit logging of temporary
tables is conditionally performed. If the binlog_format==ROW and
thd->is_current_stmt_binlog_format_row() is true then DROPs are
not logged. Given that the user can switch from STMT to ROW, this
is wrong because the server cannot tell, just by relying on the
ROW binlog format, that the tables have been dropped before. This
is effectively similar to the MIXED scenario when a switch from
STMT to ROW is triggered.
We fix this by removing this condition from
close_temporary_tables.
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.
Problem: SQL and IO thread were racing for the IO_CACHE. The former to
flush it, the latter to close it. In some cases this would cause the
SQL thread to lock an invalid IO_CACHE mutex (it had been destroyed by
IO thread). This would happen when SQL thread was initializing the
master.info
Solution: We solve this by locking the log and checking if it is
hot. If it is we keep the log while seeking. Otherwise we release it
right away, because a log can get from hot to cold, but not from cold
to hot.
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()).
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.
On [Open]Solaris/x86 the FPU was not switched to 64-bit double
precision mode when the server binary was built with Sun
Studio. That caused GIS test failures due to differences in
expected and actual results.
an atomic counter"
Split the large LOCK_open section in open_table().
Do not call open_table_from_share() under LOCK_open.
Remove thd->version.
This fixes
Bug#50589 "Server hang on a query evaluated using a temporary
table"
Bug#51557 "LOCK_open and kernel_mutex are not happy together"
Bug#49463 "LOCK_table and innodb are not nice when handler
instances are created".
This patch has effect on storage engines that rely on
ha_open() PSEA method being called under LOCK_open.
In particular:
1) NDB is broken and left unfixed. NDB relies on LOCK_open
being kept as part of ha_open(), since it uses auto-discovery.
While previously the NDB open code was race-prone, now
it simply fails on asserts.
2) HEAP engine had a race in ha_heap::open() when
a share for the same table could be added twice
to the list of shares, or a dangling reference to a share
stored in HEAP handler. This patch aims to address this
problem by 'pinning' the newly created share in the
internal HEAP engine share list until at least one
handler instance is created using that share.
Item*) at opt_sum.cc:305
Queries applying MIN/MAX functions to indexed columns are
optimized to read directly from the index if all key parts
of the index preceding the aggregated key part are bound to
constants by the WHERE clause. A prefix length is also
produced, equal to the total length of the bound key
parts. If the aggregated column itself is bound to a
constant, however, it is also included in the prefix.
Such full search keys are read as closed intervals for
reasons beyond the scope of this bug. However, the procedure
missed one case where a key part meant for use as range
endpoint was being overwritten with a NULL value destined
for equality checking. In this case the key part was
overwritten but the range flag remained, causing open
interval reading to be performed.
Bug was fixed by adding more stringent checking to the
search key building procedure (matching_cond) and never
allow overwrites of range predicates with non-range
predicates.
An assertion was added to make sure open intervals are never
used with full search keys.
strict aliasing violations.
One somewhat major source of strict-aliasing violations and
related warnings is the SQL_LIST structure. For example,
consider its member function `link_in_list` which takes
a pointer to pointer of type T (any type) as a pointer to
pointer to unsigned char. Dereferencing this pointer, which
is done to reset the next field, violates strict-aliasing
rules and might cause problems for surrounding code that
uses the next field of the object being added to the list.
The solution is to use templates to parametrize the SQL_LIST
structure in order to deference the pointers with compatible
types. As a side bonus, it becomes possible to remove quite
a few casts related to acessing data members of SQL_LIST.
strict aliasing violations.
Essentially, the problem is that large parts of the server were
developed in simpler times (last decades, pre C99 standard) when
strict aliasing and compilers supporting such optimizations were
rare to non-existent. Thus, when compiling the server with a modern
compiler that uses strict aliasing rules to perform optimizations,
there are several places in the code that might trigger undefined
behavior.
As evinced by some recent bugs, GCC does a somewhat good of job
misoptimizing such code, but on the other hand also gives warnings
about suspicious code. One problem is that the warnings aren't
always accurate, yet we can't afford to just shut them off as we
might miss real cases. False-positive cases are aggravated mostly
by casts that are likely to trigger undefined behavior.
The solution is to start a cleanup process focused on fixing and
reducing the amount of strict-aliasing related warnings produced
by GCC and others compilers. A good deal of noise reduction can
be achieved by just removing useless casts that are product of
historical cruft and are likely to trigger undefined behavior if
dereferenced.
make tdc_refresh_version an atomic counter".
To avoid orphaned TABLE_SHARE objects left in the
cache, make sure that wherever we set table->s->version
we take care of removing all unused table share objects
from the table cache.
Always set table->s->version under LOCK_open, to make sure
that no other connection sees an old value of the
version and adds the table to unused_tables list.
Add an assert to table_def_unuse_table() that we never
'unuse' a talbe of a share that has an old version.
With this patch, only three places are left in the code
that manipulate with table->s->version:
- tdc_remove_table(). In most cases we have an X mdl lock
in tdc_remove_table(), the two remaining cases when we
don't are 'FLUSH TABLE' and mysql_admin_table().
- sql_view.cc - a crude hack that needs a separate fix
- initial assignment from refresh_version in table.cc.
Problem: the server missed the fact that one can read from
2 indexes alternately using HANDLER interface.
Fix: check if the same (initialized) index is involved
reading next/prev values from the index.
mutex protecting thd->open_tables".
We should not manipulate with table->s->version outside the
table definition cache code, but use the TDC API
to achieve the desired result.
Fix one violation: close_all_tables_for_name().
Bug#46527 COMMIT AND CHAIN RELEASE does not make sense
Bug#53343 completion_type=1, COMMIT/ROLLBACK AND CHAIN don't
preserve the isolation level
Bug#53346 completion_type has strange effect in a stored
procedure/prepared statement
Added test cases to verify the expected behaviour of :
SET SESSION TRANSACTION ISOLATION LEVEL,
SET TRANSACTION ISOLATION LEVEL,
@@completion_type,
COMMIT AND CHAIN,
ROLLBACK AND CHAIN
..and some combinations of the above
