The condition over the outer tables now are extracted from
the on condition of any outer join. This condition is
saved in a special field of the JOIN_TAB structure for
the first inner table of the outer join. The condition
is checked before the first inner table is accessed. If 
it turns out to be false the table is not accessed at all
and a null complemented row is generated immediately.

Fix usage of mysqld option --new, --old, --safe and --skip_new to not disable things that are proven stable or enable things that are not usefull.


sql/field.cc:
  Remove feature of 'new_mode' that was never implemtented in a newer MySQL version.
sql/item_cmpfunc.cc:
  Boyer more is stable; Don't have to be protected by --skip-new anymore
sql/mysqld.cc:
  Don't disable some proven stable functions with --skip-new
sql/records.cc:
  Don't disable record caching with --safe-mode anymore
sql/sql_delete.cc:
  Do fast truncate even if --skip-new or --safe is used
sql/sql_parse.cc:
  Use always mysql_optimizer() for optimizer (instead of mysql_recreate_table() in case of --safe or --skip-new)
sql/sql_select.cc:
  Don't disable 'only_eq_ref_tables' if --safe is used.
sql/sql_yacc.yy:
  Removed not meaningfull test of --old

The problem could be demonstrated with an outer join of two single-row
tables where the values of the join attributes were null. Any query
with such a join could return a wrong result set if the where
condition of the query was not empty. For queries with empty
where conditions the result sets were correct.
This was the consequence of two bugs in the code:
 - Item_equal objects for on conditions of outer joins were
   not built if the processed query had no where condition
 - the check for null values in the code that evaluated constant 
   Item_equal objects was incorrect.
Fixed both above problems.
Added a test case for the bug and adjusted results for some other
test cases.

When not-exists optimization was applied to a table that
happened to be an inner table of two outer joins, one
embedded into another, then setting the match flag for
the embedding outer join on could be skipped. This caused
generation of extra null complemented rows.
Made sure that the match flags are set correctly in all cases
when not-exists optimization is used.  

Cache parameters print added in EXPLAIN EXTENDED output.

mysql-test/r/compare.result:
  Cache parameters print added in EXPLAIN EXTENDED output.
mysql-test/r/group_by.result:
  Cache parameters print added in EXPLAIN EXTENDED output.
mysql-test/r/subselect.result:
  Cache parameters print added in EXPLAIN EXTENDED output.
mysql-test/r/subselect3.result:
  Cache parameters print added in EXPLAIN EXTENDED output.
mysql-test/r/subselect3_jcl6.result:
  Cache parameters print added in EXPLAIN EXTENDED output.
mysql-test/r/subselect4.result:
  Cache parameters print added in EXPLAIN EXTENDED output.
mysql-test/r/subselect_cache.result:
  Added test suite for LP BUG#615760
mysql-test/r/subselect_mat.result:
  Cache parameters print added in EXPLAIN EXTENDED output.
mysql-test/r/subselect_no_mat.result:
  Cache parameters print added in EXPLAIN EXTENDED output.
mysql-test/r/subselect_no_opts.result:
  Cache parameters print added in EXPLAIN EXTENDED output.
mysql-test/r/subselect_no_semijoin.result:
  Cache parameters print added in EXPLAIN EXTENDED output.
mysql-test/r/subselect_sj.result:
  Cache parameters print added in EXPLAIN EXTENDED output.
mysql-test/r/subselect_sj_jcl6.result:
  Cache parameters print added in EXPLAIN EXTENDED output.
mysql-test/suite/pbxt/r/subselect.result:
  Cache parameters print added in EXPLAIN EXTENDED output.
mysql-test/t/subselect_cache.test:
  Cache parameters print added in EXPLAIN EXTENDED output.
sql/item.cc:
  Item::set_expr_cache result fixed according to its description.
  
  Cache parameters print added in EXPLAIN EXTENDED output.
sql/item.h:
  Cache parameters print added in EXPLAIN EXTENDED output.
sql/item_cmpfunc.cc:
  Check on double cache assignment added into the transformation methods.
sql/item_cmpfunc.h:
  Check on double cache assignment added into the transformation methods.
sql/item_subselect.cc:
  Check on double cache assignment added into the transformation methods.
sql/item_subselect.h:
  Check on double cache assignment added into the transformation methods.
sql/sql_expression_cache.cc:
  Cache parameters print added.
sql/sql_expression_cache.h:
  Cache parameters print added.
sql/sql_select.cc:
  Removed unused method (now it is impossible to make double transformation with the cache).
sql/sql_select.h:
  Removed unused method.

Fall back to use ALTER TABLE for engines that doesn't support REPAIR when doing repair for upgrade.
Nicer output from mysql_upgrade and mysql_check
Updated all arrays that used NAME_LEN to use SAFE_NAME_LEN to ensure that we don't break things accidently as names can now have a #mysql50# prefix.

client/mysql_upgrade.c:
  If we are using verbose, also run mysqlcheck in verbose mode.
client/mysqlcheck.c:
  Add more information if running in verbose mode
  Print 'Needs upgrade' instead of complex error if table needs to be upgraded
  Don't write connect information if verbose is not 2 or above
mysql-test/r/drop.result:
  Updated test and results as we now support full table names
mysql-test/r/grant.result:
  Now you get a correct error message if using #mysql with paths
mysql-test/r/show_check.result:
  Update results as table names can temporarly be bigger than NAME_LEN (during upgrade)
mysql-test/r/upgrade.result:
  Test upgrade for long table names.
mysql-test/suite/funcs_1/r/is_tables_is.result:
  Updated old test result (had note been updated in a while)
mysql-test/t/drop.test:
  Updated test and results as we now support full table names
mysql-test/t/grant.test:
  Now you get a correct error message if using #mysql with paths
mysql-test/t/upgrade.test:
  Test upgrade for long table names.
sql/ha_partition.cc:
  NAME_LEN -> SAFE_NAME_LEN
sql/item.cc:
  NAME_LEN -> SAFE_NAME_LEN
sql/log_event.cc:
  NAME_LEN -> SAFE_NAME_LEN
sql/mysql_priv.h:
  Added SAFE_NAME_LEN
sql/rpl_filter.cc:
  NAME_LEN -> SAFE_NAME_LEN
sql/sp.cc:
  NAME_LEN -> SAFE_NAME_LEN
sql/sp_head.cc:
  NAME_LEN -> SAFE_NAME_LEN
sql/sql_acl.cc:
  NAME_LEN -> SAFE_NAME_LEN
sql/sql_base.cc:
  NAME_LEN -> SAFE_NAME_LEN
sql/sql_connect.cc:
  NAME_LEN -> SAFE_NAME_LEN
sql/sql_parse.cc:
  NAME_LEN -> SAFE_NAME_LEN
sql/sql_prepare.cc:
  NAME_LEN -> SAFE_NAME_LEN
sql/sql_select.cc:
  NAME_LEN -> SAFE_NAME_LEN
sql/sql_show.cc:
  NAME_LEN -> SAFE_NAME_LEN
  Enlarge table names for SHOW TABLES to also include optional #mysql50#
sql/sql_table.cc:
  Fall back to use ALTER TABLE for engines that doesn't support REPAIR when doing repair for upgrade.
sql/sql_trigger.cc:
  NAME_LEN -> SAFE_NAME_LEN
sql/sql_udf.cc:
  NAME_LEN -> SAFE_NAME_LEN
sql/sql_view.cc:
  NAME_LEN -> SAFE_NAME_LEN
sql/table.cc:
  Fixed check_table_name() to not count #mysql50# as part of name
  If #mysql50# is part of the name, don't allow path characters in name.

Fix for LP#612894 Some aggregate functions (such as MIN MAX) work incorrectly in subqueries after getting NULL value


mysql-test/r/group_by.result:
  Added test that showed problems that no_rows_in_results() didn't work for expressions
mysql-test/r/subselect4.result:
  Test case for LP#612894
mysql-test/t/group_by.test:
  Added test that showed problems that no_rows_in_results() didn't work for expressions
mysql-test/t/subselect4.test:
  Test case for LP#612894
sql/item.h:
  Added restore_to_before_no_rows_in_result()
  Added function processor for no_rows_in_results() and restore_to_before_no_rows_in_results() to ensure it works with functions
  Fix that above functions are handled by Item_ref()
sql/item_func.h:
  Ensure that no_rows_in_results() and restore_to_before_no_rows_in_result() are called for all function arguments
sql/item_sum.cc:
  Added restore_to_before_no_rows_in_result() to restore settings after Item_sum_hybrid::no_rows_in_result() was called.
  This is needed to handle the case where we have made 'make_const()' on the item in opt_sum(), but the item will be reused again in a sub query.
  Ignore multiple calls to no_rows_in_result() as Item_ref is calling it twice.
sql/item_sum.h:
  Added restore_to_before_no_rows_in_result();
sql/sql_select.cc:
  Added reset of no_rows_in_result() for JOIN::reinit()
sql/sql_select.h:
  Added marker if no_rows_in_result() is called.

Changed to use longlong10_to_str() instead of longlong2str() when base is 10 or -10 as former is much faster than later
Changed my_vsnprintf() to use longlong2str instead of int2str() to get rid of warnings and to get support for long pointers even when long is 32 bit.

client/mysqltest.cc:
  longlong2str() -> longlong10_to_str()
include/m_string.h:
  Added extra argument to longlong2str() to make it have same prototype is int2str()
mysys/charset.c:
  Fixed compiler warning
mysys/mf_soundex.c:
  Fixed compiler warning
mysys/my_getopt.c:
  longlong2str() -> longlong10_to_str()
sql/create_options.cc:
  Fixed compiler warning
sql/item_strfunc.cc:
  Added extra argument to longlong2str
sql/opt_range.cc:
  longlong2str() -> longlong10_to_str()
sql/partition_info.cc:
  longlong2str() -> longlong10_to_str()
sql/slave.cc:
  longlong2str() -> longlong10_to_str()
sql/sql_bitmap.h:
  Added extra argument to longlong2str
sql/sql_partition.cc:
  Added extra argument to longlong2str
sql/sql_select.cc:
  longlong2str() -> longlong10_to_str()
sql/sql_show.cc:
  Added extra argument to longlong2str
storage/innodb_plugin/handler/ha_innodb.cc:
  Update to new parameters for longlong2str()
storage/maria/ma_dbug.c:
  longlong2str() -> longlong10_to_str()
storage/maria/maria_chk.c:
  Added extra argument to longlong2str
storage/myisam/mi_dbug.c:
  longlong2str() -> longlong10_to_str()
storage/myisam/myisamchk.c:
  Added extra argument to longlong2str
storage/xtradb/handler/ha_innodb.cc:
  Update to new parameters for longlong2str()
strings/longlong2str.c:
  Added extra argument to longlong2str() to make it have same prototype is int2str()
strings/my_vsnprintf.c:
  Changed my_vsnprintf() to use longlong2str instead of int2str() to get rid of warnings and to get support for long pointers even when long is 32 bit.
  Added cast to get rid of compiler warnings

This was triggered by innodb.innodb_multi_update, where we had a static length row without nulls and xtradb didn't fill in the delete-marker byte


include/my_bitmap.h:
  Added prototype for bitmap_union_is_set_all()
mysys/my_bitmap.c:
  Added function to check if union of two bit maps covers all bits.
sql/mysql_priv.h:
  Updated protype for compare_record()
sql/sql_insert.cc:
  Send to compare_record() flag if all fields are used.
sql/sql_select.cc:
  Set share->null_bytes_for_compare.
sql/sql_update.cc:
  In compare_record() don't use the fast cmp_record() (which is basically memcmp) if we don't know that all fields exists.
  Don't compare the null_bytes if there is no data there.
sql/table.cc:
  Store in share->null_bytes_for_compare the number of bytes that has null or bit fields (but not delete marker)
  Store in can_cmp_whole_record if we can use memcmp() (assuming all rows are read) to compare rows in compare_record()
sql/table.h:
  Added two elements in table->share to speed up checking how updated rows can be compared.

check_join_cache_usage() by the change:

Revno: 2793
Revision Id: igor@askmonty.org-20091221022615-kx5ieiu0okmiupuc
Timestamp: Sun 2009-12-20 18:26:15 -0800

Backport into MariaDB-5.2 the following:
WL#2771 "Block Nested Loop Join and Batched Key Access Join"

The command CREATE TABLE AS SELECT erroneously preserved the virtual
properties of the virtual fields from the select list. 

For queries with order by clauses that employed filesort usage of
virtual column references in select lists could trigger assertion
failures. It happened because a wrong vcol_set bitmap was used for
filesort. It turned out that filesort required its own vcol_set bitmap.

Made management of the vcol_set bitmaps similar to the management
of the read_set and write_set bitmaps.  

This assert checks that the server does not try to send OK to the
client if there has been some error during processing. This is done
to make sure that the error is in fact sent to the client.

The problem was that view errors during processing of WHERE conditions
in UPDATE statements where not detected by the update code. It therefore
tried to send OK to the client, triggering the assert.
The bug was only noticeable in debug builds.

This patch fixes the problem by making sure that the update code
checks for errors during condition processing and acts accordingly.

If the expression for a virtual column of table contained datetime
comparison then the execution of the second query that used this
virtual column caused a crash. It happened because the execution
of the first query that used this virtual column inserted a cached
item into the expression tree. The cached tree was allocated in
the statement memory while the expression tree was allocated in
the table memory.
Now the cached items that are inserted into expressions for virtual
columns with datetime comparisons are always allocated in the same
mem_root as the expressions for virtual columns. So now the inserted
cached items are valid for any queries that use these virtual columns. 

The issue was that we didn't always check result of ha_rnd_init() which caused a problem for handlers that returned an error in this code.
- Changed prototype of ha_rnd_init() to ensure that we get a compile warning if result is not checked.
- Added ha_rnd_init_with_error() that prints error on failure.
- Checked all usage of ha_rnd_init() and ensure we generate an error message on failures.
- Changed init_read_record() to return 1 on failure.




sql/create_options.cc:
  Fixed wrong printf
sql/event_db_repository.cc:
  Check result from init_read_record()
sql/events.cc:
  Check result from init_read_record()
sql/filesort.cc:
  Check result from ha_rnd_init()
sql/ha_partition.cc:
  Check result from ha_rnd_init()
sql/ha_partition.h:
  Fixed compiler warning
sql/handler.cc:
  Added ha_rnd_init_with_error()
  Check result from ha_rnd_init()
sql/handler.h:
  Added ha_rnd_init_with_error()
  Changed prototype of ha_rnd_init() to ensure that we get a compile warning if result is not checked
sql/item_subselect.cc:
  Check result from ha_rnd_init()
sql/log.cc:
  Check result from ha_rnd_init()
sql/log_event.cc:
  Check result from ha_rnd_init()
sql/log_event_old.cc:
  Check result from ha_rnd_init()
sql/mysql_priv.h:
  init_read_record() now returns error code on failure
sql/opt_range.cc:
  Check result from ha_rnd_init()
sql/records.cc:
  init_read_record() now returns error code on failure
  Check result from ha_rnd_init()
sql/sql_acl.cc:
  Check result from init_read_record()
sql/sql_cursor.cc:
  Print error if ha_rnd_init() fails
sql/sql_delete.cc:
  Check result from init_read_record()
sql/sql_help.cc:
  Check result from init_read_record()
sql/sql_plugin.cc:
  Check result from init_read_record()
sql/sql_select.cc:
  Check result from ha_rnd_init()
  Print error if ha_rnd_init() fails.
sql/sql_servers.cc:
  Check result from init_read_record()
sql/sql_table.cc:
  Check result from init_read_record()
sql/sql_udf.cc:
  Check result from init_read_record()
sql/sql_update.cc:
  Check result from init_read_record()
storage/example/ha_example.cc:
  Don't return error on rnd_init()
storage/ibmdb2i/ha_ibmdb2i.cc:
  Removed not relevant comment

subquery execution, where the the REF buffer format was mistaken to
be in record format instead of key format. The error was that the null
byte for all fields of the record was in the front of the buffer,
and not before each field data.

libmysqld/Makefile.am:
  The new file added.
mysql-test/r/index_merge_myisam.result:
  subquery_cache optimization option added.
mysql-test/r/myisam_mrr.result:
  subquery_cache optimization option added.
mysql-test/r/subquery_cache.result:
  The subquery cache tests added.
mysql-test/r/subselect3.result:
  Subquery cache switched off to avoid changing read statistics.
mysql-test/r/subselect3_jcl6.result:
  Subquery cache switched off to avoid changing read statistics.
mysql-test/r/subselect_no_mat.result:
  subquery_cache optimization option added.
mysql-test/r/subselect_no_opts.result:
  subquery_cache optimization option added.
mysql-test/r/subselect_no_semijoin.result:
  subquery_cache optimization option added.
mysql-test/r/subselect_sj.result:
  subquery_cache optimization option added.
mysql-test/r/subselect_sj_jcl6.result:
  subquery_cache optimization option added.
mysql-test/t/subquery_cache.test:
  The subquery cache tests added.
mysql-test/t/subselect3.test:
  Subquery cache switched off to avoid changing read statistics.
sql/CMakeLists.txt:
  The new file added.
sql/Makefile.am:
  The new files added.
sql/item.cc:
  Expression cache item (Item_cache_wrapper) added.
  Item_ref and Item_field fixed for correct usage of result field and fast resolwing in SP.
sql/item.h:
  Expression cache item (Item_cache_wrapper) added.
  Item_ref and Item_field fixed for correct usage of result field and fast resolwing in SP.
sql/item_cmpfunc.cc:
  Subquery cache added.
sql/item_cmpfunc.h:
  Subquery cache added.
sql/item_subselect.cc:
  Subquery cache added.
sql/item_subselect.h:
  Subquery cache added.
sql/item_sum.cc:
  Registration of subquery parameters added.
sql/mysql_priv.h:
  subquery_cache optimization option added.
sql/mysqld.cc:
  subquery_cache optimization option added.
sql/opt_range.cc:
  Fix due to subquery cache.
sql/opt_subselect.cc:
  Parameters of the function cahnged.
sql/procedure.h:
  .h file guard added.
sql/sql_base.cc:
  Registration of subquery parameters added.
sql/sql_class.cc:
  Option to allow add indeces to temporary table.
sql/sql_class.h:
  Item iterators added.
  Option to allow add indeces to temporary table.
sql/sql_expression_cache.cc:
  Expression cache for caching subqueries added.
sql/sql_expression_cache.h:
  Expression cache for caching subqueries added.
sql/sql_lex.cc:
  Registration of subquery parameters added.
sql/sql_lex.h:
  Registration of subqueries and subquery parameters added.
sql/sql_select.cc:
  Subquery cache added.
sql/sql_select.h:
  Subquery cache added.
sql/sql_union.cc:
  A new parameter to the function added.
sql/sql_update.cc:
  A new parameter to the function added.
sql/table.cc:
  Procedures to manage temporarty tables index added.
sql/table.h:
  Procedures to manage temporarty tables index added.
storage/maria/ha_maria.cc:
  Fix of handler to allow destoy a table in case of error during the table creation.
storage/maria/ha_maria.h:
  .h file guard added.
storage/myisam/ha_myisam.cc:
  Fix of handler to allow destoy a table in case of error during the table creation.

The problem there is that HAVING condition evaluates const
parts of condition despite the condition has references
on aggregate functions. Table t1 became const tables
after make_join_statistics and table1.pk = 1, HAVING is
transformed into MAX(1) < 7 and taken away from HAVING.
The fix is to skip evaluation of HAVING conts parts if
HAVING condition has references on aggregate functions.


mysql-test/r/having.result:
  test case
mysql-test/t/having.test:
  test case
sql/sql_select.cc:
  skip evaluation of HAVING conts parts if
  HAVING condition has references on aggregate functions.

- Item_in_subselect::init_left_expr_cache() should not try to 
  guess whether the left expression is accessed "over the grouping operation"
  (i.e. the subselect is evaluated after the grouping while the left_expr is
   an Item_ref that wraps an expression from before the grouping). Instead, 
  let new_Cached_item not to try accessing item->real_item() when creating 
  left expr cache.

The problem is that QUICK_SELECT_DESC behaviour depends
on used_key_parts value which can be bigger than selected
best_key_parts value if an engine supports clustered key.
But used_key_parts is overwritten with best_key_parts
value that prevents from correct selection of index
access method. The fix is to preserve used_key_parts
value for further use in QUICK_SELECT_DESC.


mysql-test/r/innodb_mysql.result:
  test case
mysql-test/t/innodb_mysql.test:
  test case
sql/sql_select.cc:
  preserve used_key_parts value for further use in QUICK_SELECT_DESC

- fix a bug in LooseScan strategy execution code (exposed by changing costs/QEP)
- Do set join_tab->sorted=TRUE for JOIN_TABs that use LooseScan (partitioning 
   handler cares about "sorted" parameter of h->index_init() call)

file .\filesort.cc, line 149 (part II)

Problem: the server didn't disregard sort order 
for some zero length tuples.

Fix: skip sort order in such a case 
(zero length NOT NULL string functions).


mysql-test/r/select.result:
  Fix for bug #54459: Assertion failed: param.sort_length, 
  file .\filesort.cc, line 149 (part II)
    - test result.
mysql-test/t/select.test:
  Fix for bug #54459: Assertion failed: param.sort_length, 
  file .\filesort.cc, line 149 (part II)
    - test case.
sql/sql_select.cc:
  Fix for bug #54459: Assertion failed: param.sort_length, 
  file .\filesort.cc, line 149 (part II)
    - disregard sort order for zero length NOT NULL string functions
  along with zero length NOT NULL fields.

> ------------------------------------------------------------
> revno: 3351.41.1
> revision-id: alexey.kopytov@sun.com-20100430111048-jdls6ofn4kkmpt09
> parent: sergey.glukhov@sun.com-20100329134249-03wyhzp5k92dzhcb
> committer: Alexey Kopytov <Alexey.Kopytov@Sun.com>
> branch nick: my51-bug48419
> timestamp: Fri 2010-04-30 15:10:48 +0400
> message:
>   Bug #48419: another explain crash..
>   
>   WHERE predicates containing references to empty tables in a
>   subquery were handled incorrectly by the optimizer when
>   executing EXPLAIN. As a result, the optimizer could try to
>   evaluate such predicates rather than just stop with
>   "Impossible WHERE noticed after reading const tables" as 
>   it would do in a non-subquery case. This led to valgrind 
>   errors and crashes.
>   
>   Fixed the code checking the above condition so that subqueries
>   are not excluded and hence are handled in the same way as top
>   level SELECTs.

            strict aliasing violations.

One somewhat major source of strict-aliasing violations and
related warnings is the SQL_LIST structure. For example,
consider its member function `link_in_list` which takes
a pointer to pointer of type T (any type) as a pointer to
pointer to unsigned char. Dereferencing this pointer, which
is done to reset the next field, violates strict-aliasing
rules and might cause problems for surrounding code that
uses the next field of the object being added to the list.

The solution is to use templates to parametrize the SQL_LIST
structure in order to deference the pointers with compatible
types. As a side bonus, it becomes possible to remove quite
a few casts related to acessing data members of SQL_LIST.

sql/handler.h:
  Use the appropriate template type argument.
sql/item.cc:
  Remove now-unnecessary cast.
sql/item_subselect.cc:
  Remove now-unnecessary casts.
sql/item_sum.cc:
  Use the appropriate template type argument.
  Remove now-unnecessary cast.
sql/mysql_priv.h:
  Move SQL_LIST structure to sql_list.h
  Use the appropriate template type argument.
sql/sp.cc:
  Remove now-unnecessary casts.
sql/sql_delete.cc:
  Use the appropriate template type argument.
  Remove now-unnecessary casts.
sql/sql_derived.cc:
  Remove now-unnecessary casts.
sql/sql_lex.cc:
  Remove now-unnecessary casts.
sql/sql_lex.h:
  SQL_LIST now takes a template type argument which must
  match the type of the elements of the list. Use forward
  declaration when the type is not available, it is used
  in pointers anyway.
sql/sql_list.h:
  Rename SQL_LIST to SQL_I_List. The template parameter is
  the type of object that is stored in the list.
sql/sql_olap.cc:
  Remove now-unnecessary casts.
sql/sql_parse.cc:
  Remove now-unnecessary casts.
sql/sql_prepare.cc:
  Remove now-unnecessary casts.
sql/sql_select.cc:
  Remove now-unnecessary casts.
sql/sql_show.cc:
  Remove now-unnecessary casts.
sql/sql_table.cc:
  Remove now-unnecessary casts.
sql/sql_trigger.cc:
  Remove now-unnecessary casts.
sql/sql_union.cc:
  Remove now-unnecessary casts.
sql/sql_update.cc:
  Remove now-unnecessary casts.
sql/sql_view.cc:
  Remove now-unnecessary casts.
sql/sql_yacc.yy:
  Remove now-unnecessary casts.
storage/myisammrg/ha_myisammrg.cc:
  Remove now-unnecessary casts.

* remove handler::index_read_last()
* create handler::keyread_read_time() (was get_index_only_read_time() in opt_range.cc)
* ha_show_status() allows engine's show_status() to fail
* remove HTON_FLUSH_AFTER_RENAME
* fix key_cmp_if_same() to work for floats and doubles
* set table->status in the server, don't force engines to do it
* increment status vars in the server, don't force engines to do it

mysql-test/r/status_user.result:
  correct test results - innodb was wrongly counting internal
  index searches as handler_read_* calls.
sql/ha_partition.cc:
  compensate for handler incrementing status counters -
  we want to count only calls to underlying engines
sql/handler.h:
  inline methods moved to sql_class.h
sql/key.cc:
  simplify the check
sql/opt_range.cc:
  move get_index_only_read_time to the handler class
sql/sp.cc:
  don't use a key that's stored in the record buffer -
  the engine can overwrite the buffer with anything, destroying the key
sql/sql_class.h:
  inline handler methods that need to see THD and TABLE definitions
sql/sql_select.cc:
  no ha_index_read_last_map anymore
sql/sql_table.cc:
  remove HTON_FLUSH_AFTER_RENAME
sql/table.cc:
  set HA_CAN_MEMCMP as appropriate
sql/tztime.cc:
  don't use a key that's stored in the record buffer -
  the engine can overwrite the buffer with anything, destroying the key
storage/myisam/ha_myisam.cc:
  engines don't need to update table->status or use ha_statistic_increment anymore
storage/myisam/ha_myisam.h:
  index_read_last_map is no more

There are two problems:
1. In simplify_joins function we calculate table dependencies. If STRAIGHT_JOIN hint
is used for whole SELECT we do not count it and as result some dependendecies
might be lost. It leads to incorrect table order which is returned by
join_tab_cmp_straight() function.
2. make_join_statistics() calculate the transitive closure for relations a particular
JOIN_TAB is 'dependent on'.
We aggregate the dependent table_map of a JOIN_TAB by adding dependencies from other
tables which we depend on. However, this may also cause new dependencies to be
available after we have completed processing a certain JOIN_TAB.
Both these problems affect condition pushdown and as result condition might be pushed
into wrong table which leads to crash or even omitted which leads to wrong result.
The fix:
1. Use modified 'transitive closure' algorithm provided by Ole John Aske
2. Update table dependences in simplify_joins according to 
   global STRAIGHT_JOIN hint.
Note: the patch also fixes bugs 46091 & 51492


mysql-test/r/join_outer.result:
  test case
mysql-test/t/join_outer.test:
  test case
sql/sql_select.cc:
  1. Use modified 'transitive closure' algorithm provided by Ole John Aske
  2. Update table dependences in simplify_joins according to 
     global STRAIGHT_JOIN hint.

Bug #39022: completed
Bug #39653: reverted as invalid
Bug #45640: ameliorated, simplified, optimized
Bug #48483: completed
Bug #49324: improved
Bug #51242/52336: reverted, applied a real fix.

- INSERT with RAND() doesn't require row based logging again
- Some bugs fixed in opt_range() where we table->key_read was wrongly used



.bzrignore:
  Ignore new xtstat binary
mysql-test/r/index_merge_myisam.result:
  Update results (old result was wrong)
mysql-test/suite/binlog/r/binlog_stm_binlog.result:
  Added drop table first
mysql-test/suite/binlog/r/binlog_stm_unsafe_warning.result:
  Added test for when RAND() requires row based logging
mysql-test/suite/binlog/t/binlog_stm_binlog.test:
  Added drop table first
mysql-test/suite/binlog/t/binlog_stm_unsafe_warning.test:
  Added test for when RAND() requires row based logging
scripts/make_binary_distribution.sh:
  Removed type from last commit
sql/item_create.cc:
  Don't require row based logging when using RAND() with INSERT
sql/opt_range.cc:
  Revert wrong patch from Oracle:
  - As QUICK_RANGE_SELECT uses it's own 'file' handler to the tables, one can't use 'table->key_read' as a flag to detect if index only read (keyread) is used or not
  - Don't set keyread if keyread is already enabled
  - Don't disable key read, if we didn't enable it ourselves
  - Simplify code (and ensure that we do proper cleanup of index only read)
sql/opt_range.h:
  Added flags to detect if the range optimizer enabled index only read (key read) or not
sql/opt_sum.cc:
  Use our more optimized macros
sql/sql_lex.h:
  Added 'readable' function to check if we are in a sub query function or not (not normal query or sub query in FROM clause)
sql/sql_select.cc:
  Use our more optimized keyread macros
  Added ASSERTS early
  Simplify code on eliminate_item_equal()
  Fixed that substitute_for_best_equal_field() doesn't core dump in case of out of memory conditions.
  Removed not needed test for 'field->maybe_null()'
  Replaced master_unit()->item with is_subquery_function() (More readable)
sql/sql_update.cc:
  Use our more optimized keyread macros
sql/table.cc:
  Use our more optimized keyread macros
sql/table.h:
  Use separate functions to enable/disable Index only reads
  - Safer, more readable, better logging and faster.

tests still fail, the fix will come from 5.1 tree

The fix actually reverts the change introduced
by the patch for bug 51494.
The fact is that patches for bugs 52177&48419
fix bugs 51194&50575 as well.



mysql-test/r/innodb_mysql.result:
  test case
mysql-test/t/innodb_mysql.test:
  test case
sql/sql_select.cc:
  reverted wrong fix for bug 51494

greedy_search optimizer_search_depth=0

The algorithm inside restore_prev_nj_state failed to
properly update the counters within the NESTED_JOIN
tree. The counter was decremented each time a table in the
node was removed from the QEP, the correct thing to do being
only to decrement it when the last table in the child node
was removed from the plan. This lead to node counters
getting negative values and the plan thus appeared
impossible. An assertion caught this.

Fixed by not recursing up the tree unless the last table in
the join nest node is removed from the plan

The fix actually reverts the change introduced by the patch
for bug 51494
The fact is that the patch for bug 52177 fixes bug 51194 as well.

WHERE predicates containing references to empty tables in a
subquery were handled incorrectly by the optimizer when
executing EXPLAIN. As a result, the optimizer could try to
evaluate such predicates rather than just stop with
"Impossible WHERE noticed after reading const tables" as 
it would do in a non-subquery case. This led to valgrind 
errors and crashes.

Fixed the code checking the above condition so that subqueries
are not excluded and hence are handled in the same way as top
level SELECTs.

mysql-test/r/explain.result:
  Added a test case for bug #48419.
mysql-test/r/ps.result:
  Updated test results to take the new (and more correct)
  "Extra" comments in execution plans.
mysql-test/t/explain.test:
  Added a test case for bug #48419.
sql/sql_select.cc:
  There is no point in excluding subqueries from checking
  for identically false WHERE conditions.

The problem was in an incorrect debug assertion. The expression
used in the failing assertion states that when finding
references matching ORDER BY expressions, there can be only one
reference to a single table. But that does not make any sense,
all test cases for this bug are valid examples with multiple
identical WHERE expressions referencing the same table which
are also present in the ORDER BY list.

Fixed by removing the failing assertion. We also have to take
care of the 'found' counter so that we count multiple
references only once. We rely on this fact later in
eq_ref_table().

mysql-test/r/join.result:
  Added a test case for bug #50335.
mysql-test/t/join.test:
  Added a test case for bug #50335.
sql/sql_select.cc:
  Removing the assertion in eq_ref_table() as it does not make
  any sense. We also have to take care of the 'found' counter so
  that we count multiple references only once. We rely on this
  fact later in eq_ref_table().

union...order by (select... where...)

The problem is mysql is trying to materialize and 
cache the scalar sub-queries at JOIN::optimize
even for EXPLAIN where the number of columns is 
totally different from what's expected.
Fixed by not executing the scalar subqueries 
for EXPLAIN.

The problem is that we can not use make_cond_for_table().
This function relies on used_tables() condition
which is not set properly for subqueries.
As result subquery is not filtered out.
The fix is to use remove_eq_conds() function instead
of make_cond_for_table() func. 'remove_eq_conds()'
algorithm relies on const_item() value and it allows
to handle subqueries in right way.


mysql-test/r/having.result:
  test case
mysql-test/t/having.test:
  test case
sql/sql_select.cc:
  The fix is to use remove_eq_conds() function instead
  of make_cond_for_table() function.