Description: When the table has more than one unique or primary key,
INSERT... ON DUP KEY UPDATE statement is sensitive to the order in which
the storage engines checks the keys. Depending on this order, the storage
engine may determine different rows to mysql, and hence mysql can update
different rows on master and slave.
Solution: We mark INSERT...ON DUP KEY UPDATE on a table with more than on unique
key as unsafe therefore the event will be logged in row format if it is available
(ROW/MIXED). If only STATEMENT format is available, a warning will be thrown.
Background:
- as described in MySQL Internals Prepared Stored
(http://forge.mysql.com/wiki/MySQL_Internals_Prepared_Stored),
the Optimizer sometimes does destructive changes to the parsed
LEX-object (Item-tree), which makes it impossible to re-use
that tree for PS/SP re-execution.
- in order to be able to re-use the Item-tree, the destructive
changes are remembered and rolled back after the statement execution.
The problem, discovered by this bug, was that the objects representing
GROUP-BY clause did not restored after query execution. So, the GROUP-BY
part of the statement could not be properly re-initialized for re-execution
after destructive changes.
Those objects do not take part in the Item-tree, so they can not be saved
using the approach for Item-tree.
The fix is as follows:
- introduce a new array in st_select_lex to store the original
ORDER pointers, representing the GROUP-BY clause;
- Initialize this array in fix_prepare_information().
- restore the list of GROUP-BY items in reinit_stmt_before_use().
Fix the calculation of the next autoinc value when offset > 1. Some of the
results have changed due to the changes in the allocation calculation. The
new calculation will result in slightly bigger gaps for bulk inserts.
rb://866 Approved by Jimmy Yang.
Backported from mysql-trunk (5.6)
LOCK_THREAD_COUNT
When using the performance schema file io instrumentation in MySQL 5.5,
a thread would loop forever inside lf_pinbox_put_pins, when disconnecting.
It would also hold LOCK_thread_count while doing so, effectively killing the
server.
The root cause of the loop in lf_pinbox_put_pins() is a leak of LF_PINS,
when used with the filename_hash LF_HASH table in the performance schema.
This fix contains the following changes:
1)
Added the missing call to lf_hash_search_unpin(), to prevent the leak.
2)
In mysys/lf_alloc-pin.c, there was some extra debugging code
(MY_LF_EXTRA_DEBUG) written to detect precisely this kind of issues,
but it was never used.
Replaced MY_LF_EXTRA_DEBUG with DBUG_OFF, so that leaks similar to this one
can be always detected in regular debug builds.
3)
Backported the fix for the following bug, from 5.6 to 5.5:
Bug#13417446 - 63339: INCORRECT FILE PATH IN PEFORMANCE_SCHEMA ON WINDOWS
HANG IN PREPARING WITH 100% CPU USAGE
Infinite loop in the subselect_indexsubquery_engine::exec()
function caused Server hang with 100% CPU usage.
The BLACKHOLE storage engine didn't update handler's
table->status variable after index operations, that
caused an infinite "while(!table->status)" execution.
Index access methods of the BLACKHOLE engine handler
have been updated to set table->status variable to
STATUS_NOT_FOUND or 0 when such a method returns a
HA_ERR_END_OF_FILE error or 0 respectively.
Analysis:
-------------------------------
According to the Manual
(http://dev.mysql.com/doc/refman/5.1/en/identifier-case-sensitivity.html):
"Column, index, stored routine, and event names are not case sensitive on any
platform, nor are column aliases."
In other words, 'lower_case_table_names' does not affect the behaviour of
those identifiers.
On the other hand, trigger names are case sensitive on some platforms,
and case insensitive on others. 'lower_case_table_names' does not affect
the behaviour of trigger names either.
The bug was that SHOW statements did case sensitive comparison
for stored procedure / stored function / event names.
Fix:
Modified the code so that comparison in case insensitive for routines
and events for "SHOW" operation.
As part of this commit, only fixing the test failures due to the actual code fix.
Change the type of purge_sys_t::n_pages_handled and purge_sys_t::handle_limit
to ulonglong from ulint. On a 32 bit system doing ~700 deletes per second the
counters can overflow in ~3.5 months, if they are 32 bit.
Approved by Jimmy Yang over IM.
Analysis:
-------------------------------
According to the Manual
(http://dev.mysql.com/doc/refman/5.1/en/identifier-case-sensitivity.html):
"Column, index, stored routine, and event names are not case sensitive on any
platform, nor are column aliases."
In other words, 'lower_case_table_names' does not affect the behaviour of
those identifiers.
On the other hand, trigger names are case sensitive on some platforms,
and case insensitive on others. 'lower_case_table_names' does not affect
the behaviour of trigger names either.
The bug was that SHOW statements did case sensitive comparison
for stored procedure / stored function / event names.
Fix:
Modified the code so that comparison in case insensitive for routines
and events for "SHOW" operation.
rb://942
approved by: Marko Makela
We don't need to scan LRU for dropping AHI entries when DROPing a table.
AHI entries are already removed when we free up extents for the btree.
Problem:
Field_set::val_str in case of an empty SET value
returned a String with str_length==0 and Ptr==0,
which is not expected by some pieces of the code.
Fix:
Returning an empty string with str_length==0 and Ptr=="",
like Field_enum does.
The test case must insert all the records using a single transaction. Otherwise the test
case takes more than 15 minutes and will time out in pb2 and mtr.
FROM BUFFER POOL
rb://975
approved by: Marko Makela
There is a race in lock_validate() where we try to access a page
without ensuring that the tablespace stays valid during the operation
i.e.: it is not deleted. This patch tries to fix that by using an
existing flag (the flag is renamed to make it's name more generic
in line with it's new use).
IN OS_THREAD_EQ
rb://977
approved by: Marko Makela
rw_lock::writer_thread field contains the thread id of current x-holder
or wait-x thread. This field is un-initialized at lock creation and is
written to for the first time when an attempt is made to x-lock.
Current code considers ::writer_thread as valid memory region only when
the lock is held in x-mode (or there is an x-waiter). This is an
overkill and it generates valgrind warnings.
The fix is to consider ::writer_thread as valid memory region once it
has been written to.
Reasoning:
==========
The ::writer_thread can be safely considered valid because:
* We only ever do comparison with current calling threads id.
* We only ever do comparison when ::recursive flag is set
* We always unset ::recursive flag in x-unlock
* Same thread cannot be unlocking and attempting to lock at the same
time
* thread_id recycling is not an issue because before an id is recycled
the thread must leave innodb meaning it must release all locks meaning
it must unset ::recursive flag.
AND SAVEPOINT.
The bug was introduced by the patch for bug#11766752. This patch sets too
strong condition on XA state for SAVEPOINT statement that disallows its
execution during XA transaction. But since the statement SAVEPOINT doesn't
imply implicit commit we can allow its handling during XA transaction.
The patch explicitly check for transaction state against states XA_NOTR
and XA_ACTIVE for which the handling of statement SAVEPOINT for XA
transaction is allowed.
The table contains one time value: '00:00:32'
This value is converted to timestamp by a subquery.
In convert_constant_item we call (*item)->is_null()
which triggers execution of the Item_singlerow_subselect subquery,
and the string "0000-00-00 00:00:32" is cached
by Item_cache_datetime.
We continue execution and call update_null_value, which calls val_int()
on the cached item, which converts the time value to ((longlong) 32)
Then we continue to do (*item)->save_in_field()
which ends up in Item_cache_datetime::val_str() which fails,
since (32 < 101) in number_to_datetime, and val_str() returns NULL.
Item_singlerow_subselect::val_str isnt prepared for this:
if exec() succeeds, and return !null_value, then val_str()
*must* succeed.
Solution: refuse to cache strings like "0000-00-00 00:00:32"
in Item_cache_datetime::cache_value, and return NULL instead.
This is similar to the solution for
Bug#11766860 - 60085: CRASH IN ITEM::SAVE_IN_FIELD() WITH TIME DATA TYPE
This patch is for 5.5 only.
The issue is not present after WL#946, since a time value
will be converted to a proper timestamp, with the current date
rather than "0000-00-00"
