The LGPL license is used in some legacy code, and to
adhere to current licensing polity, we remove those
files that are no longer used, and reorganize the
remaining LGPL code so it will be GPL licensed from
now on.
Note: This patch only removed LGPL licensed files
in MySQL 5.5 and later, and is the third of a
set of patches to remove LGPL from all trees.
(See Bug# 11840513 for details)
The LGPL license is used in some legacy code, and to
adhere to current licensing polity, we remove those
files that are no longer used, and reorganize the
remaining LGPL code so it will be GPL licensed from
now on.
Note: This patch only removed LGPL licensed files
in MySQL 5.1, and is the second of a set of
patches to remove LGPL from all trees.
(See Bug# 11840513 for details)
When executing row-ordered-retrieval index merge,
the handler was cloned, but it used the wrong
memory root, so instead of allocating memory
on the thread/query's mem_root, it used the table's
mem_root, resulting in non released memory in the
table object, and was not freed until the table was
closed.
Solution was to ensure that memory used during cloning
of a handler was allocated from the correct memory root.
This was implemented by fixing handler::clone() to also
take a name argument, so it can be used with partitioning.
And in ha_partition only allocate the ha_partition's ref, and
call the original ha_partition partitions clone() and set at cloned
partitions.
Fix of .bzrignore on Windows with VS 2010
MAP 'REPAIR TABLE' TO RECREATE +ANALYZE FOR ENGINES NOT
SUPPORTING NATIVE REPAIR
Executing 'mysqlcheck --check-upgrade --auto-repair ...' will first issue
'CHECK TABLE FOR UPGRADE' for all tables in the database in order to check if the
tables are compatible with the current version of MySQL. Any tables that are
found incompatible are then upgraded using 'REPAIR TABLE'.
The problem was that some engines (e.g. InnoDB) do not support 'REPAIR TABLE'.
This caused any such tables to be left incompatible. As a result such tables were
not properly fixed by the mysql_upgrade tool.
This patch fixes the problem by first changing 'CHECK TABLE FOR UPGRADE' to return
a different error message if the engine does not support REPAIR. Instead of
"Table upgrade required. Please do "REPAIR TABLE ..." it will report
"Table rebuild required. Please do "ALTER TABLE ... FORCE ..."
Second, the patch changes mysqlcheck to do 'ALTER TABLE ... FORCE' instead of
'REPAIR TABLE' in these cases.
This patch also fixes 'ALTER TABLE ... FORCE' to actually rebuild the table.
This change should be reflected in the documentation. Before this patch,
'ALTER TABLE ... FORCE' was unused (See Bug#11746162)
Test case added to mysqlcheck.test
client/mysqlcheck.c:
Changed mysqlcheck to do 'ALTER TABLE ... FORCE' if
'CHECK TABLE FOR UPGRADE' reports ER_TABLE_NEEDS_REBUILD
and not ER_TABLE_NEEDS_UPGRADE.
mysql-test/r/mysqlcheck.result:
Added regression test.
mysql-test/std_data/bug47205.frm:
InnoDB 5.0 FRM which contains a varchar primary key using
utf8_general_ci. This is an incompatible FRM for 5.5.
mysql-test/t/mysqlcheck.test:
Added regression test.
sql/handler.h:
Added new HA_CAN_REPAIR flag.
sql/share/errmsg-utf8.txt:
Added new error message ER_TABLE_NEEDS_REBUILD
sql/sql_admin.cc:
Changed 'CHECK TABLE FOR UPDATE' to give ER_TABLE_NEEDS_REBUILD
instead of ER_TABLE_NEEDS_UPGRADE if the engine does not support
REPAIR (as indicated by the new HA_CAN_REPAIR flag).
sql/sql_lex.h:
Remove unused ALTER_FORCE flag.
sql/sql_yacc.yy:
Make sure ALTER TABLE ... FORCE recreates the table
by setting the ALTER_RECREATE flag as the ALTER_FORCE
flag was unused.
storage/archive/ha_archive.h:
Added new HA_CAN_REPAIR flag to Archive
storage/csv/ha_tina.h:
Added new HA_CAN_REPAIR flag to CSV
storage/federated/ha_federated.h:
Added new HA_CAN_REPAIR flag to Federated
storage/myisam/ha_myisam.cc:
Added new HA_CAN_REPAIR flag to MyISAM
- MWL#47, allowing to annotate row-based binlog events with the SQL test of
the originating query (eg. in mysqlbinlog output).
- row_based_replication_without_primary_key.patch, providing more intelligent
selection of index to use on slave when applying row-based binlog events
for tables with no primary key.
- Make mysqlbinlog omit redundant `use` around BEGIN/SAVEPOINT/COMMIT/
ROLLBACK in 5.0 binlogs.
This will also enable us in the future to collect statistics for
writes to internal tmp tables.
sql/handler.h:
Added ha_write_tmp_row()
sql/opt_subselect.cc:
ha_write_row -> ha_write_tmp_row
sql/sql_class.h:
Added ha_write_tmp_row()
sql/sql_select.cc:
ha_write_row -> ha_write_tmp_row
mysql-test/suite/handler/innodb.result:
Added test case
mysql-test/suite/handler/innodb.test:
Added test case
sql/handler.h:
Move setting/resetting of active_index to ha_index_init()/ha_index_end() to simplify handler functions index_init()/index_end()
Fixed that get_index() returns MAX_KEY if index is not inited (this fixed LP#697610)
storage/federated/ha_federated.cc:
Settting of active_index is not needed anymore
storage/maria/ma_pagecache.c:
Added error message if we have too little memory for Maria page cache
that implement add_index
The problem was that ALTER TABLE blocked reads on an InnoDB table
while adding a secondary index, even if this was not needed. It is
only needed for the final step where the .frm file is updated.
The reason queries were blocked, was that ALTER TABLE upgraded the
metadata lock from MDL_SHARED_NO_WRITE (which blocks writes) to
MDL_EXCLUSIVE (which blocks all accesses) before index creation.
The way the server handles index creation, is that storage engines
publish their capabilities to the server and the server determines
which of the following three ways this can be handled: 1) build a
new version of the table; 2) change the existing table but with
exclusive metadata lock; 3) change the existing table but without
metadata lock upgrade.
For InnoDB and secondary index creation, option 3) should have been
selected. However this failed for two reasons. First, InnoDB did
not publish this capability properly.
Second, the ALTER TABLE code failed to made proper use of the
information supplied by the storage engine. A variable
need_lock_for_indexes was set accordingly, but was not later used.
This patch fixes this problem by only doing metadata lock upgrade
before index creation/deletion if this variable has been set.
This patch also changes some of the related terminology used
in the code. Specifically the use of "fast" and "online" with
respect to ALTER TABLE. "Fast" was used to indicate that an
ALTER TABLE operation could be done without involving a
temporary table. "Fast" has been renamed "in-place" to more
accurately describe the behavior.
"Online" meant that the operation could be done without taking
a table lock. However, in the current implementation writes
are always prohibited during ALTER TABLE and an exclusive
metadata lock is held while updating the .frm, so ALTER TABLE
is not completely online. This patch replaces "online" with
"in-place", with additional comments indicating if concurrent
reads are allowed during index creation/deletion or not.
An important part of this update of terminology is renaming
of the handler flags used by handlers to indicate if index
creation/deletion can be done in-place and if concurrent reads
are allowed. For example, the HA_ONLINE_ADD_INDEX_NO_WRITES
flag has been renamed to HA_INPLACE_ADD_INDEX_NO_READ_WRITE,
while HA_ONLINE_ADD_INDEX is now HA_INPLACE_ADD_INDEX_NO_WRITE.
Note that this is a rename to clarify current behavior, the
flag values have not changed and no flags have been removed or
added.
Test case added to innodb_mysql_sync.test.
- Added test case for Aria
- Tested HANDLER with HEAP (changes to HEAP code will be pushed in 5.3)
- Moved all HANDLER test to suite/handler.
mysql-test/Makefile.am:
Added suite/handler
mysql-test/mysql-test-run.pl:
Added suite/handler
mysql-test/r/lock_multi.result:
Remove test that is already in handler test suite
mysql-test/suite/handler/aria.result:
Test for HANDLER with Aria storage engine
mysql-test/suite/handler/aria.test:
Test for HANDLER with Aria storage engine
mysql-test/suite/handler/handler.inc:
Extended the general handler test
Moved interface testing to 'interface.test'
mysql-test/suite/handler/init.inc:
Common init for handler tests.
mysql-test/suite/handler/innodb.result:
New results
mysql-test/suite/handler/innodb.test:
Update to use new include files
mysql-test/suite/handler/interface.result:
Test of HANDLER interface (not storage engine dependent parts)
mysql-test/suite/handler/interface.test:
Test of HANDLER interface (not storage engine dependent parts)
mysql-test/suite/handler/myisam.result:
New results
mysql-test/suite/handler/myisam.test:
Update to use new include files
mysql-test/t/lock_multi.test:
Remove test that is already in handler test suite
mysys/tree.c:
Added missing handling of read previous (showed up in HEAP testing)
sql/handler.cc:
Don't marka 'HA_ERR_RECORD_CHANGED' as fatal (can be used with HANDLER READ, especially with MEMORY ENGINE)
sql/handler.h:
Added prototype for can_continue_handler_scan()
sql/sql_handler.cc:
Re-initialize search if we switch from key to table search.
Check if handler can continue searching between calls (via can_continue_handler_scan())
Don't write common not fatal errors to log
storage/maria/ma_extra.c:
Don't set index 0 as default. This forces call to ma_check_index() to set up index variables.
storage/maria/ma_ft_boolean_search.c:
Ensure that info->last_key.keyinfo is set
storage/maria/ma_open.c:
Don't set index 0 as default. This forces call to ma_check_index() to set up index variables.
storage/maria/ma_rkey.c:
Trivial optimization
storage/maria/ma_rnext.c:
Added missing code from mi_rnext.c to ensure that handler next/prev works.
storage/maria/ma_rsame.c:
Simple optimizations
storage/maria/ma_search.c:
Initialize info->last_key once and for all when we change keys.
storage/maria/ma_unique.c:
Ensure that info->last_key.keyinfo is up to date.
* move a capability from a virtual handler method to table_flags()
* rephrase error messages to avoid hard-coded English parts
* admit in test cases that they need xtradb, not innodb
mysql-test/suite/vcol/t/rpl_vcol.test:
this test needs xtradb, it will fail with innodb
mysql-test/suite/vcol/t/vcol_blocked_sql_funcs_innodb.test:
this test needs xtradb, it will fail with innodb
mysql-test/suite/vcol/t/vcol_column_def_options_innodb.test:
this test needs xtradb, it will fail with innodb
mysql-test/suite/vcol/t/vcol_handler_innodb.test:
this test needs xtradb, it will fail with innodb
mysql-test/suite/vcol/t/vcol_ins_upd_innodb.test:
this test needs xtradb, it will fail with innodb
mysql-test/suite/vcol/t/vcol_keys_innodb.test:
this test needs xtradb, it will fail with innodb
mysql-test/suite/vcol/t/vcol_non_stored_columns_innodb.test:
this test needs xtradb, it will fail with innodb
mysql-test/suite/vcol/t/vcol_partition_innodb.test:
this test needs xtradb, it will fail with innodb
mysql-test/suite/vcol/t/vcol_select_innodb.test:
this test needs xtradb, it will fail with innodb
mysql-test/suite/vcol/t/vcol_supported_sql_funcs_innodb.test:
this test needs xtradb, it will fail with innodb
mysql-test/suite/vcol/t/vcol_trigger_sp_innodb.test:
this test needs xtradb, it will fail with innodb
mysql-test/suite/vcol/t/vcol_view_innodb.test:
this test needs xtradb, it will fail with innodb
sql/ha_partition.h:
check_if_supported_virtual_columns() -> HA_CAN_VIRTUAL_COLUMNS
sql/handler.h:
check_if_supported_virtual_columns() -> HA_CAN_VIRTUAL_COLUMNS
sql/share/errmsg.txt:
no hard-coded english parts in the error messages (ER_UNSUPPORTED_ACTION_ON_VIRTUAL_COLUMN)
sql/sql_table.cc:
no hard-coded english parts in the error messages
sql/table.cc:
* check_if_supported_virtual_columns() -> HA_CAN_VIRTUAL_COLUMNS
* no "csv workaround" is needed
* no hard-coded english parts in the error messages
storage/maria/ha_maria.cc:
check_if_supported_virtual_columns() -> HA_CAN_VIRTUAL_COLUMNS
storage/maria/ha_maria.h:
check_if_supported_virtual_columns() -> HA_CAN_VIRTUAL_COLUMNS
storage/myisam/ha_myisam.cc:
check_if_supported_virtual_columns() -> HA_CAN_VIRTUAL_COLUMNS
storage/myisam/ha_myisam.h:
check_if_supported_virtual_columns() -> HA_CAN_VIRTUAL_COLUMNS
storage/xtradb/handler/ha_innodb.cc:
check_if_supported_virtual_columns() -> HA_CAN_VIRTUAL_COLUMNS
storage/xtradb/handler/ha_innodb.h:
check_if_supported_virtual_columns() -> HA_CAN_VIRTUAL_COLUMNS
- Fixed problem with oqgraph and 'make dist'
Note that after this merge we have a problem show in join_outer where we examine too many rows in one specific case (related to BUG#57024).
This will be fixed when mwl#128 is merged into 5.3.
- Changed Cached_item_field not copy data for fields with NULL value
- In key_copy() and key_restore() don't copy data for fields with NULL value
Fixed code to avoid valgrind warnings
- Use c_ptr_safe instead of c_ptr()
Removed "QQ" from comments (QQ was ment to be used for internal comments that should be removed before pushing)
Fixed wrong alias used (from previous patch)
sql/event_db_repository.cc:
Update testing if event table is valid (to avoid valgrind errors)
sql/ha_partition.cc:
m_ordered_scan_ongoing was not initialized
Reset null bits in record to avoid valgrind errors
sql/handler.h:
Added flag if storage engine will write row verbatim and the row contains varchar or null fields
(in which case we must clear the row to avoid valgrind warnings)
sql/item_buff.cc:
Changed Cached_item_field not copy data for fields with NULL value
(Optimization and avoids valgrind warnings)
sql/item_func.cc:
c_ptr() -> c_ptr_safe()
sql/key.cc:
In key_copy() and key_restore() don't copy data for fields with NULL value
sql/opt_range.cc:
c_ptr() -> c_ptr_safe()
sql/sql_base.cc:
Added TRASH() to table->record[0] to find out if we access not initialzed data.
Initialize null_bytes to:
- Get consistent tests
- Ensure we don't get valgrind warnings for null fields (as we may only update a couple of bits in a byte)
sql/sql_class.cc:
Removed "QQ" from comments
sql/sql_insert.cc:
Initialize row to default values if we are using valgrind and row will be copied verbatim to disk in storage engine.
sql/sql_load.cc:
QQ -> TODO
sql/sql_parse.cc:
Removed old not used code marked QQ and withing "#ifdef REMOVED"
sql/sql_select.cc:
QQ -> TODO
Initialize some variables that was used uninitialized
Added DBUG_ASSERT() to find out if thd was not properly initialized for sub queries
sql/sql_test.cc:
Fixed format for printing to DBUG file
Fixed wrong alias used (from previous patch)
sql/sql_trigger.h:
QQ -> TODO
sql/table.cc:
QQ -> TODO
storage/maria/ha_maria.cc:
Mark table with HA_RECORD_MUST_BE_CLEAN_ON_WRITE, if row is written verbatim to disk and contains varchar or null fields.
storage/maria/ma_open.c:
Added flags if table has varchar or null fields
storage/maria/maria_def.h:
Added flags if table has varchar or null fields
storage/myisam/ha_myisam.cc:
Mark table with HA_RECORD_MUST_BE_CLEAN_ON_WRITE, if row is written verbatim to disk and contains varchar or null fields.
storage/myisam/mi_open.c:
Fixed memory overrun bug when using fulltext keys
storage/xtradb/row/row0sel.c:
Removed initialization of null bits. (not needed anymore)
Removed wrong call to translog_buffer_unlock() that caused 'unlocking not locked mutex' failure in Aria log handler.
extra/replace.c:
Updated call to my_redel()
include/maria.h:
Updated prototype for maria_change_to_newfile
include/my_sys.h:
Updated prototypes
Added my_create_backup_name
include/myisam.h:
Updated prototypes
include/myisamchk.h:
Added 'backup_time' to st_handler_check_param to be able to generate same name for backuped data and index file
mysys/my_redel.c:
Added time_t option to my_redel() to be able to generate same backup extensions for many files
sql/handler.cc:
Added start_time to st_ha_check_opt
sql/handler.h:
Added start_time to HA_CHECK_OPT
sql/mysqld.cc:
Added option BACKUP_ALL to --myisam-recover
storage/maria/ha_maria.cc:
Remember start time for repair
storage/maria/ma_check.c:
Use remembered start time for backup file names
Removed some dead code
storage/maria/ma_loghandler.c:
Removed wrong call to translog_buffer_unlock() that caused 'unlocking not locked mutex' failure in log handler.
storage/maria/maria_chk.c:
Removed dead code (O_NEW_INDEX was never set)
Report if table was 'crashed on repair'
storage/maria/maria_pack.c:
Updated parameters to my_redel()
storage/myisam/ha_myisam.cc:
Added recover option BACKUP_ALL to get a backup of the index file before it's repaired.
Print information to log if we make a backup of data as part of repair.
storage/myisam/ha_myisam.h:
Added HA_RECOVER_FULL_BACKUP
storage/myisam/mi_check.c:
Use remembered start time for backup file names
Added mi_make_backup_of_index()
storage/myisam/myisamchk.c:
Removed dead code (O_NEW_INDEX was never set)
Report if table was 'crashed on repair'
storage/myisam/myisampack.c:
Updated call to my_redel()
It was possible to issue an ALTER TABLE ADD PRIMARY KEY on
an partitioned InnoDB table that failed and crashed the server.
The problem was that it succeeded to create the PK on at least
one partition, and then failed on a subsequent partition, due to
duplicate key violation. Since the partitions that already had added
the PK was not reverted all partitions was not consistent with the
table definition, which caused the crash.
The solution was to add a revert step to ha_partition::add_index()
that dropped the index for the already succeeded partitions, on failure.
mysql-test/r/partition.result:
updated result
mysql-test/t/partition.test:
Added test
sql/ha_partition.cc:
Only allow ADD/DROP flags in pairs, so that they can be reverted on failures.
If add_index() fails for a partition, revert (drop the index) for the previous
partitions.
sql/handler.h:
Added some extra info in a comment.
BUG#26447 prefer a clustered key for an index scan, as secondary index is always slower
... which was fixed to cause
BUG#35850 queries take 50% longer
... and was reverted
and
BUG#39653 prefer a secondary index for an index scan, as clustered key is always slower
... which was fixed to cause
BUG#55656 mysqldump takes six days instead of half an hour
... and was amended with a special case workaround
sql/opt_range.cc:
move get_index_only_read_time() into the handler class
sql/sql_select.cc:
use cost not an index length when choosing a cheaper index
Bug#54678: InnoDB, TRUNCATE, ALTER, I_S SELECT, crash or deadlock
- Incompatible change: truncate no longer resorts to a row by
row delete if the storage engine does not support the truncate
method. Consequently, the count of affected rows does not, in
any case, reflect the actual number of rows.
- Incompatible change: it is no longer possible to truncate a
table that participates as a parent in a foreign key constraint,
unless it is a self-referencing constraint (both parent and child
are in the same table). To work around this incompatible change
and still be able to truncate such tables, disable foreign checks
with SET foreign_key_checks=0 before truncate. Alternatively, if
foreign key checks are necessary, please use a DELETE statement
without a WHERE condition.
Problem description:
The problem was that for storage engines that do not support
truncate table via a external drop and recreate, such as InnoDB
which implements truncate via a internal drop and recreate, the
delete_all_rows method could be invoked with a shared metadata
lock, causing problems if the engine needed exclusive access
to some internal metadata. This problem originated with the
fact that there is no truncate specific handler method, which
ended up leading to a abuse of the delete_all_rows method that
is primarily used for delete operations without a condition.
Solution:
The solution is to introduce a truncate handler method that is
invoked when the engine does not support truncation via a table
drop and recreate. This method is invoked under a exclusive
metadata lock, so that there is only a single instance of the
table when the method is invoked.
Also, the method is not invoked and a error is thrown if
the table is a parent in a non-self-referencing foreign key
relationship. This was necessary to avoid inconsistency as
some integrity checks are bypassed. This is inline with the
fact that truncate is primarily a DDL operation that was
designed to quickly remove all data from a table.
mysql-test/suite/innodb/t/innodb-truncate.test:
Add test cases for truncate and foreign key checks.
Also test that InnoDB resets auto-increment on truncate.
mysql-test/suite/innodb/t/innodb.test:
FK is not necessary, test is related to auto-increment.
Update error number, truncate is no longer invoked if
table is parent in a FK relationship.
mysql-test/suite/innodb/t/innodb_mysql.test:
Update error number, truncate is no longer invoked if
table is parent in a FK relationship.
Use delete instead of truncate, test is used to check
the interaction of FKs, triggers and delete.
mysql-test/suite/parts/inc/partition_check.inc:
Fix typo.
mysql-test/suite/sys_vars/t/foreign_key_checks_func.test:
Update error number, truncate is no longer invoked if
table is parent in a FK relationship.
mysql-test/t/mdl_sync.test:
Modify test case to reflect and ensure that truncate takes
a exclusive metadata lock.
mysql-test/t/trigger-trans.test:
Update error number, truncate is no longer invoked if
table is parent in a FK relationship.
sql/ha_partition.cc:
Reorganize the various truncate methods. delete_all_rows is now
passed directly to the underlying engines, so as truncate. The
code responsible for truncating individual partitions is moved
to ha_partition::truncate_partition, which is invoked when a
ALTER TABLE t1 TRUNCATE PARTITION p statement is executed.
Since the partition truncate no longer can be invoked via
delete, the bitmap operations are not necessary anymore. The
explicit reset of the auto-increment value is also removed
as the underlying engines are now responsible for reseting
the value.
sql/handler.cc:
Wire up the handler truncate method.
sql/handler.h:
Introduce and document the truncate handler method. It assumes
certain use cases of delete_all_rows.
Add method to retrieve the list of foreign keys referencing a
table. Method is used to avoid truncating tables that are
parent in a foreign key relationship.
sql/share/errmsg-utf8.txt:
Add error message for truncate and FK.
sql/sql_lex.h:
Introduce a flag so that the partition engine can detect when
a partition is being truncated. Used to give a special error.
sql/sql_parse.cc:
Function mysql_truncate_table no longer exists.
sql/sql_partition_admin.cc:
Implement the TRUNCATE PARTITION statement.
sql/sql_truncate.cc:
Change the truncate table implementation to use the new truncate
handler method and to not rely on row-by-row delete anymore.
The truncate handler method is always invoked with a exclusive
metadata lock. Also, it is no longer possible to truncate a
table that is parent in some non-self-referencing foreign key.
storage/archive/ha_archive.cc:
Rename method as the description indicates that in the future
this could be a truncate operation.
storage/blackhole/ha_blackhole.cc:
Implement truncate as no operation for the blackhole engine in
order to remain compatible with older releases.
storage/federated/ha_federated.cc:
Introduce truncate method that invokes delete_all_rows.
This is required to support partition truncate as this
form of truncate does not implement the drop and recreate
protocol.
storage/heap/ha_heap.cc:
Introduce truncate method that invokes delete_all_rows.
This is required to support partition truncate as this
form of truncate does not implement the drop and recreate
protocol.
storage/ibmdb2i/ha_ibmdb2i.cc:
Introduce truncate method that invokes delete_all_rows.
This is required to support partition truncate as this
form of truncate does not implement the drop and recreate
protocol.
storage/innobase/handler/ha_innodb.cc:
Rename delete_all_rows to truncate. InnoDB now does truncate
under a exclusive metadata lock.
Introduce and reorganize methods used to retrieve the list
of foreign keys referenced by a or referencing a table.
storage/myisammrg/ha_myisammrg.cc:
Introduce truncate method that invokes delete_all_rows.
This is required in order to remain compatible with earlier
releases where truncate would resort to a row-by-row delete.
Tweak the commit_ordered() semantics. Now it is only called for transactions
that go through 2-phase commit. This avoids forcing engines to make commits
visible before they are durable.
Also take LOCK_commit_ordered() around START TRANSACTION WITH CONSISTENT
SNAPSHOT, to get a truly consistent snapshot.
- Changed to still use bcmp() in certain cases becasue
- Faster for short unaligneed strings than memcmp()
- Bettern when using valgrind
- Changed to use my_sprintf() instead of sprintf() to get higher portability for old systems
- Changed code to use MariaDB version of select->skip_record()
- Removed -%::SCCS/s.% from Makefile.am:s to remove automake warnings
'CREATE TABLE IF NOT EXISTS ... SELECT' behaviour
BUG#47132, BUG#47442, BUG49494, BUG#23992 and BUG#48814 will disappear
automatically after the this patch.
BUG#55617 is fixed by this patch too.
This is the 5.5 part.
It implements:
- 'CREATE TABLE IF NOT EXISTS ... SELECT' statement will not insert
anything and binlog anything if the table already exists.
It only generate a warning that table already exists.
- A couple of test cases for the behavior changing.
