causing update of a different column

For efficiency some storage engines do not read a complete record
for update, but only the columns required for selecting the rows.

When updating a row of a partitioned table, modifying a column
that is part of the partition or subpartition expression, then
the row may need to move from one [sub]partition to another one.
This is done by inserting the new row into the target
[sub]partition and deleting the old row from the originating one.
For the insert we need a complete record.

If an above mentioned engine was used for a partitioned table, we
did not have a complete record in update_row(). The implicitly
executed write_row() got an incomplete record.

This is solved by instructing the engine to read a complete record
if one of the columns of the partition or subpartiton is to be
updated.

No testcase. This can be reproduced with Falcon only. The engines
contained in standard 5.1 do always return complete records on
update.

fixes test breakage on sles10-ia64-a which omits charset.

into  mysql.com:/home/svoj/devel/mysql/BUG29299/mysql-5.1-engines

into  mysql.com:/home/svoj/devel/mysql/BUG29299/mysql-5.0-engines

into  anubis.xiphis.org:/usr/home/antony/work/mysql-5.1-merge

Fixed warnings
Fixed error numbers

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

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

into  magare.gmz:/home/kgeorge/mysql/autopush/B29157-5.1-opt

into  synthia.local:/home/mydev/mysql-5.1-axmrg

into  synthia.local:/home/mydev/mysql-5.0-axmrg

into  synthia.local:/home/mydev/mysql-5.1-axmrg

into  synthia.local:/home/mydev/mysql-5.1-axmrg

into  synthia.local:/home/mydev/mysql-5.1-axmrg

into  anubis.xiphis.org:/usr/home/antony/work/5.0-engines-merge

pointer into a BOOL type.

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

When a UNION statement forced conversion of an UTF8
charset value to a binary charset value, the byte
length of the result values was truncated to the
CHAR_LENGTH of the original UTF8 value.

into  anubis.xiphis.org:/usr/home/antony/work/5.0-engines-merge

into  anubis.xiphis.org:/usr/home/antony/work/p2-bug25513.5

into  synthia.local:/home/mydev/mysql-5.0-axmrg

into  synthia.local:/home/mydev/mysql-5.0-axmrg

into  synthia.local:/home/mydev/mysql-5.1-axmrg

into  moonbone.local:/mnt/gentoo64/work/29261-bug-5.0-opt-mysql

spaces.

When the my_strnncollsp_simple function compares two strings and one is a prefix
of another then this function compares characters in the rest of longer key
with the space character to find whether the longer key is greater or less.
But the sort order of the collation isn't used in this comparison. This may
lead to a wrong comparison result, wrongly created index or wrong order of the
result set of a query with the ORDER BY clause.

Now the my_strnncollsp_simple function uses collation sort order to compare
the characters in the rest of longer key with the space character.

into  magare.gmz:/home/kgeorge/mysql/autopush/B27333-gcov-5.0-opt

query / no aggregate of subquery
 The optimizer counts the aggregate functions that 
 appear as top level expressions (in all_fields) in 
 the current subquery. Later it makes a list of these
 that it uses to actually execute the aggregates in
 end_send_group().
 That count is used in several places as a flag whether
 there are aggregates functions.
 While collecting the above info it must not consider
 aggregates that are not aggregated in the current 
 context. It must treat them as normal expressions 
 instead. Not doing that leads to incorrect data about
 the query, e.g. running a query that actually has no
 aggregate functions as if it has some (and hence is
 expected to return only one row).
 Fixed by ignoring the aggregates that are not aggregated
 in the current context. 
 One other smaller omission discovered and fixed in the 
 process : the place of aggregation was not calculated for
 user defined functions. Fixed by calling 
 Item_sum::init_sum_func_check() and 
 Item_sum::check_sum_func() as it's done for the rest of 
 the aggregate functions.

into  mysql.com:/home/hf/work/29247/my51-29247

into  mysql.com:/home/hf/work/29247/my50-29247

into  mysql.com:/home/hf/work/29247/my51-29247

into  mysql.com:/home/hf/work/29247/my51-29247

  "Federared Transactions Failure"
  Bug occurs when the user performs an operation which inserts more than 
  one row into the federated table and the federated table references a 
  remote table stored within a transactional storage engine. When the
  insert operation for any one row in the statement fails due to 
  constraint violation, the federated engine is unable to perform 
  statement rollback and so the remote table contains a partial commit. 
  The user would expect a statement to perform the same so a statement 
  rollback is expected.
  This bug was fixed by implementing  bulk-insert handling into the
  federated storage engine. This will relieve the bug for most common
  situations by enabling the generation of a multi-row insert into the
  remote table and thus permitting the remote table to perform 
  statement rollback when neccessary.
  The multi-row insert is limited to the maximum packet size between 
  servers and should the size overflow, more than one insert statement 
  will be sent and this bug will reappear. Multi-row insert is disabled
  when an "INSERT...ON DUPLICATE KEY UPDATE" is being performed.
  The bulk-insert handling will offer a significant performance boost 
  when inserting a large number of small rows.
This patch builds on Bug29019 and Bug25511

  "Federated INSERT failures"
  Federated does not correctly handle "INSERT...ON DUPLICATE KEY UPDATE"
  However, implementing such support is not reasonably possible without
  increasing complexity of the storage engine: checking that constraints
  on remote server match local server and parsing error messages.
  This patch causes 'ON DUPLICATE KEY' to fail with ER_DUP_KEY message
  if a conflict occurs and not to fail silently.

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.