Sometimes the number of really updated rows (with changed
column values) cannot be determined at the server level
alone (e.g. if the storage engine does not return enough
column values to verify that). So the only dependable way
in such cases is to let the storage engine return that
information if possible.
Fixed the bug at server level by providing a way for the 
storage engine to return information about wether it 
actually updated the row or the old and the new column 
values are the same. It can do that by returning 
HA_ERR_RECORD_IS_THE_SAME in ha_update_row().
Note that each storage engine may choose not to try to
return this status code, so this behaviour remains 
storage engine specific.

into  mysql.com:/home/hf/work/29156/my51-29156

don't free thd->lex->sphead if we didn't do lex_start(),
as we can have garbage there

into  mysql.com:/home/hf/work/28430/my51-28430

In the ha_partition::position we don't calculate the number of
the partition of the record. We use m_last_part_value instead relying on
that it is set in other place like previous calls of ::write_row().
In replication we do neither of these calls before ::position().
Delete_row_log_event::do_exec_row calls find_and_fetch_row() where
we used position() & rnd_pos() calls to find the record for the
PARTITION/INNODB table as it posesses InnoDB table flags.
Fixed by removing HA_PRIMARY_KEY_REQUIRED_FOR_POSITION flag from PARTITION

into  dl145s.mysql.com:/dev/shm/mhansson/my51-bug28677

into  gleb.loc:/home/uchum/work/bk/5.1-opt

into  gleb.loc:/home/uchum/work/bk/5.1-opt

into  dl145s.mysql.com:/dev/shm/mhansson/my51-bug28677

into  mysql.com:/home/hf/work/27084/my51-27084

into  gleb.loc:/home/uchum/work/bk/5.1-opt

into  gleb.loc:/home/uchum/work/bk/5.0-opt

into  gleb.loc:/home/uchum/work/bk/5.0-opt

into  gleb.loc:/home/uchum/work/bk/5.1-opt

into  gleb.loc:/home/uchum/work/bk/4.1-opt

into  olga.mysql.com:/home/igor/mysql-5.1-opt

  Merge with 5.1.

into  gleb.loc:/home/uchum/work/bk/5.1-opt

into  olga.mysql.com:/home/igor/dev-opt/mysql-5.0-opt-bug25602

into  gleb.loc:/home/uchum/work/bk/5.0-opt

the loose scan optimization for grouping queries was applied returned 
a wrong result set when the query was used with the SQL_BIG_RESULT
option.

The SQL_BIG_RESULT option forces to use sorting algorithm for grouping
queries instead of employing a suitable index. The current loose scan
optimization is applied only for one table queries when the suitable
index is covering. It does not make sense to use sort algorithm in this
case. However the create_sort_index function does not take into account
the possible choice of the loose scan to implement the DISTINCT operator
which makes sorting unnecessary. Moreover the current implementation of
the loose scan for queries with distinct assumes that sorting will
never happen. Thus in this case create_sort_index should not call
the function filesort.

into  gleb.loc:/home/uchum/work/bk/5.1-opt

into  gleb.loc:/home/uchum/work/bk/5.0-opt

into  gleb.loc:/home/uchum/work/bk/5.1-opt

into  gleb.loc:/home/uchum/work/bk/5.0-opt

INSERT into table from SELECT from the same table
with ORDER BY and LIMIT was inserting other data
than sole SELECT ... ORDER BY ... LIMIT returns.

One part of the patch for bug #9676 improperly pushed
LIMIT to temporary table in the presence of the ORDER BY
clause.
That part has been removed.

into  trift2.:/MySQL/M51/push-5.1

into  trift2.:/MySQL/M51/push-5.1

into  trift2.:/MySQL/M50/push-5.0

into  trift2.:/MySQL/M51/push-5.1

into  maint1.mysql.com:/data/localhome/tsmith/bk/maint/51

to be run only if it is available on the machine.

into  magare.gmz:/home/kgeorge/mysql/autopush/B28400-5.0-opt

The C optimizer may decide that data access operations
through pointer of different type are not related to 
the original data (strict aliasing).
This is what happens in fetch_long_with_conversion(),
when called as part of mysql_stmt_fetch() : it tries 
to check for truncation errors by first storing float
(and other types of data) into a char * buffer and then 
accesses them through a float pointer.
This is done to prevent the effects of excess precision
when using FPU registers.
However the doublestore() macro converts a double pointer
to an union pointer. This violates the strict aliasing rule.
Fixed by making the intermediary variables volatile (
to not re-introduce the excess precision bug) and using
the intermediary value instead of the char * buffer.
Note that there can be loss of precision for both signed
and unsigned 64 bit integers converted to double and back,
so the check must stay there (even for compatibility 
reasons).
Based on the excellent analysis in bug 28400.

into  trift2.:/MySQL/M51/push-5.1

into  trift2.:/MySQL/M51/push-5.1

into  trift2.:/MySQL/M50/push-5.0

into  maint1.mysql.com:/data/localhome/tsmith/bk/maint/51