To correctly decide which predicates can be evaluated with a given table
the optimizer must know the exact set of tables that a predicate depends 
on. If that mask is too wide (refer to non-existing tables) the optimizer
can erroneously skip a predicate.
One such case of wrong table usage mask were the aggregate functions.
The have a all-1 mask (meaning depend on all tables, including non-existent
ones).
Fixed by making a real used_tables mask for the aggregates. The mask is
constructed in the following way :
1. OR the table dependency masks of all the arguments of the aggregate.
2. If all the arguments of the function are from the local name resolution 
  context and it is evaluated in the same name resolution
  context where it is referenced all the tables from that name resolution 
  context are OR-ed to the dependency mask. This is to denote that an
  aggregate function depends on the number of rows it processes.
3. Handle correctly the case of an aggregate function optimization (such that
  the aggregate function can be pre-calculated and made a constant).

Made sure that an aggregate function is never a constant (unless subject of a 
specific optimization and pre-calculation).  

One other flaw was revealed and fixed in the process : references were 
not calling the recalculation method for used_tables of their targets.


mysql-test/r/subselect3.result:
  Bug #24484: test case
mysql-test/t/subselect3.test:
  Bug #24484: test case
sql/item.h:
  Bug #24484: Item_ref must update the used tables.
sql/item_sum.cc:
  Bug #24484: correct calculation of used_tables for aggregates.
sql/item_sum.h:
  Bug #24484: correct calculation of used_tables for aggregates.
sql/opt_range.cc:
  Bug #24484: fixed ref resolution in loose index scan
sql/sql_base.cc:
  Bug #24484: moved counting of leaf tables inside 
  setup_tables_and_check_access.
sql/sql_class.h:
  Bug #24484: changed table count to more narrow type.
sql/sql_insert.cc:
  Bug #24484: moved counting of leaf tables inside 
  setup_tables_and_check_access. Substract the first
  table (and its subtables) of an INSERT statement
  from leaf_count.
sql/sql_select.cc:
  Bug #24484: correct check for aggregates

additional call of file->extra() method with HA_EXTRA_NO_CACHE parameter


mysql-test/r/information_schema.result:
  test result
mysql-test/t/information_schema.test:
  test case
sql/sql_show.cc:
  additional call of file->extra() method with HA_EXTRA_NO_CACHE parameter

into  rakia.gmz:/home/kgeorge/mysql/autopush/B23556-5.0-opt

  merge of the 5.0-opt tree


mysql-test/r/trigger.result:
  merge of the 5.0-opt tree

into  rakia.gmz:/home/kgeorge/mysql/autopush/B23556-5.0-opt


mysql-test/t/trigger.test:
  Auto merged
sql/sql_delete.cc:
  Auto merged

into  rakia.gmz:/home/kgeorge/mysql/autopush/B25551-5.0-opt


sql/sql_select.cc:
  Auto merged

The bug could cause choosing a sub-optimal execution plan for 
a single-table query if a unique index with many null keys were 
defined for the table. 
It happened because the code of the check_quick_keys function 
made an assumption that any key may occur in an unique index 
only once. Yet this is not true for keys with nulls that may 
have multiple occurrences in the index.


mysql-test/r/null_key.result:
  Fixed bug #25407
  Adjusted result after the fix.
mysql-test/r/select.result:
  Added a test case for bug #25407.
mysql-test/t/select.test:
  Added a test case for bug #25407.

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

into  mysql.com:/home/hf/work/25973/my50-25973

into  rakia.gmz:/home/kgeorge/mysql/autopush/B25575-5.0-opt


sql/mysql_priv.h:
  Auto merged
sql/sql_lex.h:
  Auto merged
sql/sql_parse.cc:
  Auto merged
sql/sql_yacc.yy:
  Auto merged
sql/table.cc:
  Auto merged

 Two problems here:

 Problem 1:

 While constructing the join columns list the optimizer does as follows:
  1. Sets the join_using_fields/natural_join members of the right JOIN 
   operand.
  2. Makes a "table reference" (TABLE_LIST) to parent the two tables.
  3. Assigns the join_using_fields/is_natural_join of the wrapper table
   using join_using_fields/natural_join of the rightmost table
  4. Sets join_using_fields to NULL for the right JOIN operand.
  5. Passes the parent table up to the same procedure on the upper 
   level.

 Step 1 overrides the the join_using_fields that are set for a nested 
 join wrapping table in step 4.
 Fixed by making a designated variable SELECT_LEX::prev_join_using to 
 pass the data from step 1 to step 4 without destroying the wrapping 
 table data.

 Problem 2:

 The optimizer checks for ambiguous columns while transforming 
 NATURAL JOIN/JOIN USING to JOIN ON. While doing that there was no
 distinction between columns that are used in the generated join
 condition (where ambiguity can be checked) and the other columns
 (where ambiguity can be checked only when resolving references
 coming from outside the JOIN construct itself).
 Fixed by allowing the non-USING columns to be present in multiple 
 copies in both sides of the join and moving the ambiguity check 
 to the place where unqualified references to the join columns are
 resolved (find_field_in_natural_join()).


mysql-test/r/join_nested.result:
  BUG#25575: ERROR 1052 (Column in from clause is ambiguous) with sub-join
   - test case
mysql-test/t/join_nested.test:
  BUG#25575: ERROR 1052 (Column in from clause is ambiguous) with sub-join
   - test case
sql/mysql_priv.h:
  BUG#25575: ERROR 1052 (Column in from clause is ambiguous) with sub-join
   - use SELECT_LEX to store the ref to JOIN USING list needed by the 
     parser
sql/sql_base.cc:
  BUG#25575: ERROR 1052 (Column in from clause is ambiguous) with sub-join
   - proper check for duplicate cols
   - more detailed debug output
sql/sql_lex.h:
  BUG#25575: ERROR 1052 (Column in from clause is ambiguous) with sub-join
   - use SELECT_LEX to store the ref to JOIN USING list needed by the 
     parser
sql/sql_parse.cc:
  BUG#25575: ERROR 1052 (Column in from clause is ambiguous) with sub-join
   - proper check for duplicate cols in JOIN USING
sql/sql_yacc.yy:
  BUG#25575: ERROR 1052 (Column in from clause is ambiguous) with sub-join
   - use SELECT_LEX to store the ref to JOIN USING list needed by the 
     parser
sql/table.cc:
  BUG#25575: ERROR 1052 (Column in from clause is ambiguous) with sub-join
   - return null if no table ref (as in nested join columns).

mysql-test/t/ps_1general.test:
  replace_result fixed

 The optimizer takes away columns from GROUP BY/DISTINCT if they constitute
 all the parts of an unique index.
 However if some of the columns can contain NULLs this cannot be done 
(because an UNIQUE index can have multiple rows with NULL values).
 Fixed by not using UNIQUE indexes with nullable columns to remove
 grouping columns from GROUP BY/DISTINCT.


mysql-test/r/distinct.result:
  Bug #25551: inconsistent behaviour in grouping NULL, depending on index type
   - test case
mysql-test/t/distinct.test:
  Bug #25551: inconsistent behaviour in grouping NULL, depending on index type
   - test case
sql/sql_select.cc:
  Bug #25551: inconsistent behaviour in grouping NULL, depending on index type
   - UNIQUE NULL indices don't guarantee GROUP BY/DISTINCT.

into  olga.mysql.com:/home/igor/dev-opt/mysql-5.0-opt-bug24987


sql/opt_sum.cc:
  Auto merged
sql/sql_select.cc:
  Manual merge

Made the function opt_sum_query to return HA_ERR_KEY_NOT_FOUND when
no matches were found (instead of -1 it returned prior this patch).
This changes allow us to avoid possible conflicts with return values
from user-defined handler methods which also may return -1. 
No particular test cases are provided with this fix.


sql/opt_sum.cc:
  Fixed bug #24987.
  Made the function opt_sum_query to return HA_ERR_KEY_NOT_FOUND when
  no matches were found (instead of -1 it returned prior this patch).
  This changes allow us to avoid possible conflicts with return values
  from user-defined handler methods which also may return -1.
sql/sql_select.cc:
  Fixed bug #24987.
  Made the function opt_sum_query to return HA_ERR_KEY_NOT_FOUND when
  no matches were found (instead of -1 it returned prior this patch).
  This changes allow us to avoid possible conflicts with return values
  from user-defined handler methods which also may return -1.

into  rakia.gmz:/home/kgeorge/mysql/autopush/B25643-5.0-opt

 Checking for NULL before calling the val_xxx()
 methods only checks for such arguments that are 
 known to be NULLs at compile time. 
 The arguments that may or may not contain
 NULLs (e.g. function calls and possibly others)
 are not checked at all.
 Fixed by first calling the val_xxx() method and
 then checking for null in SEC_TO_TIME().
 In addition QUARTER() was not returning 0 (as all the 
 val_int() functions do when processing a NULL value).


mysql-test/r/func_time.result:
  Bug #25643: SEC_TO_TIME function problem
   - test case
mysql-test/t/func_time.test:
  Bug #25643: SEC_TO_TIME function problem
   - test case
sql/item_timefunc.cc:
  Bug #25643: SEC_TO_TIME function problem
   - null handling fixed for QUARTER() and SEC_TO_TIME()

Objects of the classes Item_func_is_not_null_test and Item_func_trig_cond
must be transparent for the method Item::split_sum_func2 as these classes
are pure helpers. It means that the method Item::split_sum_func2 should
look at those objects as at pure wrappers.


mysql-test/r/subselect3.result:
  Added a test case for bug #24420.
mysql-test/t/subselect3.test:
  Added a test case for bug #24420.

into  olga.mysql.com:/home/igor/dev-opt/mysql-5.0-opt-bug24653


sql/item.h:
  Auto merged

into  mysql.com:/home/gluh/MySQL/Merge/5.0


sql/item.h:
  Auto merged
sql/sql_table.cc:
  Auto merged
sql/sql_update.cc:
  Auto merged

into  olga.mysql.com:/home/igor/dev-opt/mysql-5.0-opt-bug24653


sql/item.cc:
  Auto merged
sql/item.h:
  Auto merged
sql/item_cmpfunc.cc:
  Auto merged
sql/item_func.cc:
  Auto merged
sql/sql_select.cc:
  Auto merged
mysql-test/r/subselect.result:
  Manual merge
mysql-test/t/subselect.test:
  Manual merge
sql/filesort.cc:
  Manual merge
sql/item_cmpfunc.h:
  Manual merge
sql/item_subselect.cc:
  Manual merge

The bug report has demonstrated the following two problems.
1. If an ORDER/GROUP BY list includes a constant expression being 
optimized away and, at the same time, containing single-row
subselects that return more that one row, no error is reported.
Strictly speaking the standard allows to ignore error in this case.
Yet, now a corresponding fatal error is reported in this case.
2. If a query requires sorting by expressions containing single-row
subselects that, however, return more than one row, then the execution
of the query may cause a server crash. 
To fix this some code has been added that blocks execution of a subselect
item in case of a fatal error in the method Item_subselect::exec.


mysql-test/r/subselect.result:
  Added a test cases for bug #24653.
mysql-test/t/subselect.test:
  Added a test cases for bug #24653.
sql/filesort.cc:
  Fixed bug #24653.
  Added a check for fatal error after reading the next row from the table
  in the function find_all_keys.
sql/item.cc:
  Fixed bug #24653.
  Down-ported calculation of the attribute with_subselect of for Item objects.
sql/item.h:
  Fixed bug #24653.
  Down-ported calculation of the attribute with_subselect of for Item objects.
sql/item_cmpfunc.cc:
  Fixed bug #24653.
  Down-ported calculation of the attribute with_subselect of for Item objects.
sql/item_cmpfunc.h:
  Fixed bug #24653.
  Down-ported calculation of the attribute with_subselect of for Item objects.
sql/item_func.cc:
  Fixed bug #24653.
  Down-ported calculation of the attribute with_subselect of for Item objects.
sql/item_subselect.cc:
  Fixed bug #24653.
  Added a check for fatal error in the method Item_subselect::exec
  to block evaluation of subselects in erroneous situations.
  Down-ported calculation of the attribute with_subselect of for Item objects.
sql/sql_select.cc:
  Fixed bug #24653.
  Added a check to verify that any constant expression used
  in ORDER BY and/or GROUP BY lists which is optimized away
  does not contain subselects returning more than one row.
  If it does a fatal error is reported.

into  mockturtle.local:/home/dlenev/src/mysql-5.0-merge

into  mysql.com:/home/psergey/mysql-5.0-bug8804-r12


sql/mysqld.cc:
  Auto merged

Fixed typo problem that surfaced after the merge

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


mysql-test/t/myisam.test:
  Auto merged

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


mysql-test/r/symlink.result:
  Auto merged
mysql-test/t/symlink.test:
  Auto merged
sql/table.cc:
  Auto merged
mysql-test/r/myisam.result:
  Manually merged.
mysql-test/t/myisam.test:
  Manually merged.

identical pushed_cond_guards arrays. Allocate only one always.


mysql-test/r/subselect.result:
  BUG#24127: merge
mysql-test/t/subselect3.test:
  BUG#24127: merge

the team tree for additional investigation.

into  mockturtle.local:/home/dlenev/src/mysql-5.0-merge


mysql-test/t/disabled.def:
  Auto merged
mysql-test/t/ps.test:
  Auto merged

into  mysql.com:/home/psergey/mysql-5.0-bug8804-r12


sql/item_cmpfunc.cc:
  Auto merged
sql/item_cmpfunc.h:
  Auto merged
sql/mysql_priv.h:
  Auto merged
sql/mysqld.cc:
  Auto merged
sql/sql_lex.h:
  Auto merged
sql/sql_select.cc:
  Auto merged
mysql-test/r/subselect.result:
  Manual Merge

into  mysql.com:/home/gluh/MySQL/Merge/5.0-opt

into  chilla.local:/home/mydev/mysql-5.0-bug24607


mysql-test/r/myisam.result:
  Auto merged
mysql-test/t/myisam.test:
  Auto merged

After merge fix

into  chilla.local:/home/mydev/mysql-5.0-bug24607


mysql-test/r/myisam.result:
  Manual merged
mysql-test/t/myisam.test:
  Manual merged

Fixed test. On 32-bit machines which compile without
-DBIG_TABLES, MAX_ROWS is truncated to a 32-bit value.
Using a value below 4G is portable.


mysql-test/r/myisam.result:
  Bug#24607 - MyISAM pointer size determined incorrectly
  Fixed test results.

into  kahlann.erinye.com:/home/df/mysql/build/mysql-5.0-build-work


sql/ha_ndbcluster.cc:
  Auto merged

into  mysql.com:/home/svoj/devel/mysql/BUG24401/mysql-5.0-engines


mysql-test/r/myisam.result:
  Auto merged
mysql-test/t/myisam.test:
  Auto merged