Problem: Statements that write to tables with auto_increment columns
based on the selection from another table, may lead to master
and slave going out of sync, as the order in which the rows
are retrived from the table may differ on master and slave.
Solution: We mark writing to a table with auto_increment table
as unsafe. This will cause the execution of such statements to
throw a warning and forces the statement to be logged in ROW if
the logging format is mixed.
Changes:
1. All the statements that writes to a table with auto_increment
column(s) based on the rows fetched from another table, will now
be unsafe.
2. CREATE TABLE with SELECT will now be unsafe.
IS EXECUTED TWICE FROM P
This bug is a duplicate of bug 12567331, which was pushed to the
optimizer backporting tree on 2011-06-11. This is just a back-port of
the fix. Both test cases are included as they differ somewhat.
ALTER TABLE AFTER DROP PARTITION
Bug#13608188 - 64038: CRASH IN HANDLER::HA_THD ON ALTER TABLE AFTER
REPAIR NON-EXISTING PARTITION
Backport of bug#13357766 from -trunk to -5.5.
The state of some partitions was not reset on failure, leading
to invalid states of partitions in consequent statements.
Fixed by reverting back to original state for all partitions
if not all partition names was resolved.
Also adding extra security by forcing tables to be reopened
in case of error in mysql_alter_table.
(There is also removal of \r at the end of some lines.)
CASES RESETS DATA POINTER TO SMAL
ISSUE: Myisamchk doing sort recover
on a table reduces data_file_length.
Maximum size of data file decreases,
lesser number of rows are stored.
SOLUTION: Size of data_file_length is
fixed to the original length.
CASES RESETS DATA POINTER TO SMAL
ISSUE: Myisamchk doing sort recover
on a table reduces data_file_length.
Maximum size of data file decreases,
lesser number of rows are stored.
SOLUTION: Size of data_file_length is
fixed to the original length.
KEY HANDLING ON SUBSEQUENT CREATE TABLE IF NOT EXISTS
PROBLEM:
--------
Consider a SP routine which does CREATE TABLE
with REFERENCES clause. The first call to this routine
invokes parser and the parsed items are cached, so as
to avoid parsing for the second execution of the routine.
It is obsevered that valgrind reports a warning
upon read of thd->lex->alter_info->key_list->Foreign_key object,
which seem to be pointing to a invalid memory address
during second time execution of the routine. Accessing this object
theoretically could cause a crash.
ANALYSIS:
---------
The problem stems from the fact that for some reason
elements of ref_columns list in thd->lex->alter_info->
key_list->Foreign_key object are changed to point to
objects allocated on runtime memory root.
During the first execution of routine we create
a copy of thd->lex->alter_info object.
As part of this process we create a clones of objects in
Alter_info::key_list and of Foreign_key object in particular.
Then Foreign_key object is cloned for some reason we
perform shallow copies of both Foreign_key::ref_columns
and Foreign_key::columns list. So new instance of
Foreign_key object starts to SHARE contents of ref_columns
and columns list with the original instance.
After that as part of cloning process we call
list_copy_and_replace_each_value() for elements of
ref_columns list. As result ref_columns lists in both
original and cloned Foreign_key object start to contain
pointers to Key_part_spec objects allocated on runtime
memory root because of shallow copy.
So when we start copying of thd->lex->alter_info object
during the second execution of stored routine we indeed
encounter pointer to the Key_part_spec object allocated
on runtime mem-root which was cleared during at the end
of previous execution. This is done in sp_head::execute(),
by a call to free_root(&execute_mem_root,MYF(0));
As result we get valgrind warnings about accessing
unreferenced memory.
FIX:
----
The safest solution to this problem is to
fix Foreign_key(Foreign_key, MEM_ROOT) constructor to do
a deep copy of columns lists, similar to Key(Key, MEM_ROOT)
constructor.
Bug#13011410 CRASH IN FILESORT CODE WITH GROUP BY/ROLLUP
The assert in 13580775 is visible in 5.6 only,
but shows that all versions are vulnerable.
13011410 crashes in all versions.
filesort tries to re-use the sort buffer between invocations in order to save
malloc/free overhead.
The fix for Bug 11748783 - 37359: FILESORT CAN BE MORE EFFICIENT.
added an assert that buffer properties (num_records, record_length) are
consistent between invocations. Indeed, they are not necessarily consistent.
Fix: re-allocate the sort buffer if properties change.
BUG#13519696 - 62940: SELECT RESULTS VARY WITH VERSION AND
WITH/WITHOUT INDEX RANGE SCAN
BUG#13453382 - REGRESSION SINCE 5.1.39, RANGE OPTIMIZER WRONG
RESULTS WITH DECIMAL CONVERSION
BUG#13463488 - 63437: CHAR & BETWEEN WITH INDEX RETURNS WRONG
RESULT AFTER MYSQL 5.1.
Those are all cases where the range optimizer got it wrong
with > and >=.
Bug#12985021 SIMPLE QUERY WITH DECIMAL NUMBERS TAKE AN
When parsing the fractional part of a string which
is to be converted to double, we can stop after a few digits:
the extra digits will not contribute to the actual result anyways.
Bug#11758543 50756: BIGINT '100' MATCHES 1.001E2
Expressions of the form
BIGINT_COL <compare> <non-integer constant>
should be done either as decimal, or float.
Currently however, such comparisons are done as int,
which means that the constant may be truncated,
and yield false positives/negatives for all queries
where compare is '>' '<' '>=' '<=' '=' '!='.
BIGINT_COL IN <list of contstants>
and
BIGINT_COL BETWEEN <constant> AND <constant>
are also affected.
MEMORY LEAK.
Background:
- There are caches for stored functions and stored procedures (SP-cache);
- There is no similar cache for events;
- Triggers are cached together with TABLE objects;
- Those SP-caches are per-session (i.e. specific to each session);
- A stored routine is represented by a sp_head-instance internally;
- SP-cache basically contains sp_head-objects of stored routines, which
have been executed in a session;
- sp_head-object is added into the SP-cache before the corresponding
stored routine is executed;
- SP-cache is flushed in the end of the session.
The problem was that SP-cache might grow without any limit. Although this
was not a pure memory leak (the SP-cache is flushed when session is closed),
this is still a problem, because the user might take much memory by
executing many stored routines.
The patch fixes this problem in the least-intrusive way. A soft limit
(similar to the size of table definition cache) is introduced. To represent
such limit the new runtime configuration parameter 'stored_program_cache'
is introduced. The value of this parameter is stored in the new global
variable stored_program_cache_size that used to control the size of SP-cache
to overflow.
The parameter 'stored_program_cache' limits number of cached routines for
each thread. It has the following min/default/max values given from support:
min = 256, default = 256, max = 512 * 1024.
Also it should be noted that this parameter limits the size of
each cache (for stored procedures and for stored functions) separately.
The SP-cache size is checked after top-level statement is parsed.
If SP-cache size exceeds the limit specified by parameter
'stored_program_cache' then SP-cache is flushed and memory allocated for
cache objects is freed. Such approach allows to flush cache safely
when there are dependencies among stored routines.
This patch changes the mechanism by which the client enables a
plugin. Instead of using INSERT IGNORE to reload a plugin library,
it now uses REPLACE INTO. This allows users to load a library
multiple times replacing the existing values in the mysql.plugin
table. This allows users to replace the symbol reference to a
different dl name in the table. Thus permitting enabling of
multiple versions of the same library without first disabling
the old version.
A regression test was added to ensure this feature works.
- Reverting the patch for Bug # 12584302
The patch will be reverted in 5.1 and 5.5.
The patch will not be reverted in 5.6, the change will
be properly documented in 5.6.
- Backporting DBUG_ASSERT not to crash on '0000-01-00'
(already fixed in mysql-trunk (5.6))
Introducing new collations:
utf8_general_mysql500_ci and ucs2_general_mysql500_ci,
to reproduce behaviour of utf8_general_ci and ucs2_general_ci
from mysql-5.1.23 (and earlier).
The collations are added to simplify upgrade from mysql-5.1.23 and earlier.
Note: The patch does not make new server start over old data automatically.
Some manual upgrade procedures are assumed.
Paul: please get in touch with me to discuss upgrade procedures
when documenting this bug.
modified:
include/m_ctype.h
mysql-test/r/ctype_utf8.result
mysql-test/t/ctype_utf8.test
mysys/charset-def.c
strings/ctype-ucs2.c
strings/ctype-utf8.c
The issue is that xa.test failed sporadically on some platforms.
The reason for the test failure is a race condition in xa.test.
The race condition occures between connection that executes statement
INSERT INTO t2 SELECT FROM t1 and other connection that tries to run
statements DELETE FROM t1 and COMMIT. If COMMIT statement had been executed
before the statement INSERT INTO t2 SELECT FROM t1 was locked by lock
on table t1 (as a result of query from table t1) then the INSERT statement
is executed successfully and a following test for deadlock would failed.
This patch fixes this race condition by moving COMMIT statement after commit
of distributed transaction from concurrent session.
Fixing the 5.5 part (the 5.6 part will go in a separate commit soon).
Problem:
Item_direct_ref::get_date() incorrectly calculated its "null_value",
which made UNIX_TIMESTAMP(view_column) incorrectly return NULL
for a NOT NULL view_column.
Fix:
Make Item_direct_ref::get_date() calculate null_value
in the similar way with the other methods
(val_real,val_str,val_int,val_decimal):
copy null_value from the referenced Item.
modified:
mysql-test/r/func_time.result
mysql-test/t/func_time.test
sql/item.cc
routines.
mysqldump in xml mode did not dump routines, events or
triggers.
This patch fixes this issue by fixing the if conditions
that disallowed the dump of above mentioned objects in
xml mode, and added the required code to enable dump
in xml format.
------------------------------------------------------------
revno: 3258
committer: Jon Olav Hauglid <jon.hauglid@oracle.com>
branch nick: mysql-trunk-bug12663165
timestamp: Thu 2011-07-14 10:05:12 +0200
message:
Bug#12663165 SP DEAD CODE REMOVAL DOESN'T UNDERSTAND CONTINUE HANDLERS
When stored routines are loaded, a simple optimizer tries to locate
and remove dead code. The problem was that this dead code removal
did not work correctly with CONTINUE handlers.
If a statement triggers a CONTINUE handler, the following statement
will be executed after the handler statement has completed. This
means that the following statement is not dead code even if the
previous statement unconditionally alters control flow. This fact
was lost on the dead code removal routine, which ended up with
removing instructions that could have been executed. This could
then lead to assertions, crashes and generally bad behavior when
the stored routine was executed.
This patch fixes the problem by marking as live code all stored
routine instructions that are in the same scope as a CONTINUE handler.
Test case added to sp.test.
If init_command was incorrect, we couldn't let users execute
queries, but we couldn't report the issue to the client either
as it does not expect error messages before even sending a
command. Thus, we simply disconnected them without throwing
a clear error.
We now go through the proper sequence once (without executing
any user statements) so we can report back what the problem
is. Only then do we disconnect the user.
As always, root remains unaffected by this as init_command is
(still) not executed for them.
--FLUSH-LOG BREAKS CONSISTENCY
The transaction started by mysqldump gets committed
implicitly when flush-log is specified along with
single-transaction option, and hence can break
consistency.
This is because, COM_REFRESH is executed in order
to flush logs and starting from 5.5 this command
performs an implicit commit.
Fixed by making sure that COM_REFRESH is executed
before the transaction has started and not after it.
Note : This patch triggers following behavioral
changes in mysqldump :
1) After this patch we no longer flush logs before
dumping each database if --single-transaction
option is given like it was done before (in the
absence of --lock-all-tables and --master-data
options).
2) Also, after this patch, we start acquiring
FTWRL before flushing logs in cases when only
--single-transaction and --flush-logs are given.
It becomes safe to use mysqldump with these two
options and without --master-data parameter for
backups.
unix_timestamp() is implemented in this part of the code in place of current_time().
Also, since the pb2 machines may be extremely fast, instead of looping through the code,
we use sleep(1.1) so that the variables t0 and t1 have different values.
The time comparison using current_time() stored in an int variable was giving wrong results as
the current_time() format as an int implementation has been changed in mysql-trunk but not in mysql-5.5.
The time is stored in the format hh:mm:ss as 'time' datatype.But as an int, it is stored as hhmmss,
but only on the trunk. On mysql-5.5,as an int, it is stored as hh.
Hence, the current_time() function has been changed to unix_timestamp() function.
Problem description:
When a view is created using function FORMAT and if FORMAT function uses locale
option,definition of view saved into server doesn't contain that locale information,
Ex:
create table test2 (bb decimal (10,2));
insert into test2 values (10.32),(10009.2),(12345678.21);
create view test3 as select format(bb,1,'sk_SK') as cc from test2;
select * from test3;
+--------------+
| cc |
+--------------+
| 10.3 |
| 10,009.2 |
| 12,345,678.2 |
+--------------+
3 rows in set (0.02 sec)
show create view test3
View: test3
Create View: CREATE ALGORITHM=UNDEFINED DEFINER=`root`@`localhost`
SQL SECURITY DEFINER VIEW `test3` AS select format(`test2`.`bb`,1) AS `cc`
from `test2`
character_set_client: latin1
collation_connection: latin1_swedish_ci
1 row in set (0.02 sec)
Problem Analysis:
The function Item_func_format::print() which prints the query string to create
the view does not print the third argument (i.e the locale information). Hence
view is created without locale information.
Problem Solution:
If argument count is more than 2 we now print the third argument onto the query string.
Files changed:
sql/item_strfunc.cc
Function call changes: Item_func_format::print()
mysql-test/t/select.test
Added test case to test the bug
mysql-test/r/select.result
Result of the test case appended here
