The problem is that select queries executed concurrently with
a concurrent insert on a MyISAM table could be cached if the
select started after the query cache invalidation but before
the unlock of tables performed by the concurrent insert. This
race could happen because the concurrent insert was failing
to prevent cache of select queries happening at the same time.
The solution is to add a 'uncacheable' status flag to signal
that a concurrent insert is being performed on the table and
that queries executing at the same time shouldn't cache the
results.
connections
The problem is that tables can enter open table cache for a thread without
being properly cleaned up. This can happen if make_join_statistics() fails
to read a const table because of e.g. a deadlock. It does set a member of
TABLE structure to a value it allocates, but doesn't clean-up this setting
on error nor does it set the rest of the members in JOIN to allow for
automatic cleanup.
As a result when such an error occurs and the next statement depends re-uses
the table from the open tables cache it will get it with this
TABLE::reginfo.join_tab pointing to a memory area that's freed.
Fixed by making sure make_join_statistics() cleans up TABLE::reginfo.join_tab
on error.
In case of ROW item each compared pair does not
check if argumet collations can be aggregated and
thus appropiriate item conversion does not happen.
The fix is to add the check and convertion for ROW
pairs.
returns short string value.
Multibyte character sets were not taken into account when
calculating max_length in Item_param::convert_str_value(). As a
result, string parameters of a prepared statement could be
truncated later when calculating string length in characters by
dividing length in bytes by the charset's mbmaxlen value (e.g. in
Field_varstring::store()).
Fixed by taking charset's mbmaxlen into account when calculating
max_length in Item_param::convert_str_value().
Backport from 6.0
Changed error message to show that it is partitioning
that does not support foreign keys yet.
Changed spelling from British english to American english.
- Remove bothersome warning messages. This change focuses on the warnings
that are covered by the ignore file: support-files/compiler_warnings.supp.
- Strings are guaranteed to be max uint in length
Additional fix:
1. Revert the unification of DROP FUNCTION
and DROP PROCEDURE, because DROP FUNCTION can be used to
drop UDFs (that have a non-qualified name and don't require
database name to be present and valid).
2. Fixed the case sensitivity problem by adding a call to
check_db_name() (similar to the sp_name production).
MATCH() function accepts column list as an argument. It was possible to override
this requirement with aliased non-column select expression. Which results in
server crash.
With this fix aliased non-column select expressions are not accepted by MATCH()
function, returning an error.
Some errors that cause the slave SQL thread to stop are not shown in the
Slave_SQL_Error column of "SHOW SLAVE STATUS". Instead, the error is only
in the server's error log.
That makes it difficult to analyze the error for the user. One example of an error
that stops the slave but is not shown by "SHOW SLAVE STATUS" is when @@global.init_slave
is set incorrectly (e.g., it contains something that is not valid SQL).
Three failures were not correctly reported:
1 - Failures during slave thread initialization
2 - Failures while initializing the relay log position right after
starting the slave thread.
3 - Failures while processing queries passed through the init_slave
option.
This patch fixes the issues by reporting the errors through relay-info->report.
- Remove bothersome warning messages. This change focuses on the warnings
that are covered by the ignore file: support-files/compiler_warnings.supp.
- Strings are guaranteed to be max uint in length
The check for root-ness would signal an error. Errors would make the
server exit before usage (help) information was printed.
Now, test for whether we want help regardless of whether we're going
to exit with an error. If plugins are not initialized by the time we
print usage information, inform the user that some parameters are
missing.
date_format functions
String::realloc() did not check whether the existing string data fits in
the newly allocated buffer for cases when reallocating a String object
with external buffer (i.e.alloced == FALSE). This could lead to memory
overruns in some cases.
There is an inconsistency with DROP DATABASE IF EXISTS, DROP
TABLE IF EXISTS and DROP VIEW IF EXISTS: those are binlogged even
if the DB or TABLE does not exist, whereas DROP PROCEDURE IF
EXISTS does not. It would be nice or at least consistent if DROP
PROCEDURE/STATEMENT worked the same too.
Fixed DROP PROCEDURE|FUNCTION IF EXISTS by adding a call to
write_bin_log in mysql_execute_command. Checked also if all
documented "DROP (...) IF EXISTS" get binlogged. Left out DROP
SERVER IF EXISTS because it seems that it only gets binlogged when
using row event (see BUG#25705).
The parser was not using the correct fully-qualified-name
production for DROP FUNCTION.
Fixed by copying the production from DROP PROCEDURE.
Tested in the windows specific suite to make sure it's
tested on a case-insensitive file system.
innodb_flush_method=wrong_value causes crash
Problem: after a failed plugin initialization, incompletely
initialized data remained in the plugin and handlerton data
structures. These were used later and caused the crash.
Fix: clean-up plugin related data if initialization failed.
Note: no test case added, hand tested.
The problem is that a unfiltered user query was being passed as
the format string parameter of sql_print_warning which later
performs printf-like formatting, leading to crashes if the user
query contains formatting instructions (ie: %s). Also, it was
using THD::query as the source of the user query, but this
variable is not meaningful in some situations -- in a delayed
insert, it points to the table name.
The solution is to pass the user query as a parameter for the
format string and use the function parameter query_arg as the
source of the user query.
