------------------------------------------------------------
revno: 2630.8.3
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w4
timestamp: Thu 2008-06-05 10:48:36 +0400
message:
WL#3726 "DDL locking for all metadata objects".
After-review fixes in progress.
Adjust some comments that were using old terminology
(name locks instead of exclusive metadata locks), brought
some of them up-to-date with current situation in code.
sql/sql_base.cc:
Adjusted comments to use proper terminology.
sql/sql_delete.cc:
Adjusted comments to use proper terminology.
sql/sql_handler.cc:
Adjusted comments to use proper terminology.
sql/sql_partition.cc:
Adjusted comments to use proper terminology also fixed
one comment to correspond to what really happens in code.
sql/sql_show.cc:
Adjusted comments to use proper terminology.
sql/sql_table.cc:
Adjusted comments to use proper terminology, brought
one of them up-to-date with current situation.
sql/sql_trigger.cc:
Adjusted comments to use proper terminology.
sql/table.h:
Removed two unused members of TABLE_SHARE struct.
------------------------------------------------------------
revno: 2630.4.20
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w2
timestamp: Wed 2008-06-04 16:27:06 +0400
message:
WL#3726 "DDL locking for all metadata objects"
After review fixes in progress.
Got rid of TABLE_LIST::mdl_upgradable member and related functions
by using special flag which to be passed to open_table() which
asks it to take upgradable metadata lock on table being opened.
sql/mysql_priv.h:
Added one more argument to open_n_lock_single_table() call to be
able to pass flags to open_table() and mysql_lock_tables() called
by it.
Added new flag for controlling open_table() behavior asks it to
take upgradable metadata locks on tables open for write.
sql/sql_base.cc:
Added new flag for controlling open_table() behavior asks it to
take upgradable metadata locks on tables open for write.
This allowed us to get rid of TABLE_LIST::mdl_upgradable member.
Added one more argument to open_n_lock_single_table() call to be
able to pass flags to open_table() and mysql_lock_tables() called
by it.
sql/sql_insert.cc:
Added one more argument to open_n_lock_single_table() call to be
able to pass flags to open_table() and mysql_lock_tables() called
by it.
sql/sql_parse.cc:
Got rid of TABLE_LIST::mdl_upgradable member by using special flag
which to be passed to open_table() which asks it to take
upgradable metadata lock on table being opened. As result also
got rid of adjust_mdl_locks_upgradability() function.
sql/sql_table.cc:
Got rid of TABLE_LIST::mdl_upgradable member and related functions
by using special flag which to be passed to open_table() which
asks it to take upgradable metadata lock on table being opened.
sql/sql_view.cc:
Got rid of TABLE_LIST::mdl_upgradable member and related functions
by using special flag which to be passed to open_table() which
asks it to take upgradable metadata lock on table being opened.
sql/table.h:
Got rid of TABLE_LIST::mdl_upgradable member and related functions
by using special flag which to be passed to open_table() which
asks it to take upgradable metadata lock on table being opened.
---------------------------------------------
2630.7.3 Konstantin Osipov 2008-06-02
Various style changes preceding the removal of reopen_table().
(Post-review fixes for WL#3726).
sql/event_db_repository.cc:
Update to use the new signature of TABLE_LIST::init_one_table().
sql/mysql_priv.h:
Move close_cached_table() and wait_while_table_is_used()
to sql_base.cc.
sql/sql_base.cc:
Move close_cached_table() and wait_while_table_is_used()
from sql_table.cc.
sql/sql_table.cc:
Move close_cached_table() and wait_while_table_is_used()
to sql_base.cc.
sql/table.h:
Update the signature of TABLE_LIST::init_one_table().
------------------------------------------------------------
revno: 2630.4.17
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w2
timestamp: Thu 2008-05-29 16:52:56 +0400
message:
WL#3726 "DDL locking for all metadata objects".
After review fixes in progress.
"The great correction of names".
Renamed MDL_LOCK and MDL_LOCK_DATA classes to make usage of
these names in metadata locking subsystem consistent with
other parts of server (i.e. thr_lock.cc). Now we MDL_LOCK_DATA
corresponds to request for a lock and MDL_LOCK to the lock
itself. Adjusted code in MDL subsystem and other places
using these classes accordingly.
Did similar thing for GLOBAL_MDL_LOCK_DATA class and also
changed name of its members to correspond to names of
MDL_LOCK_DATA members.
Finally got rid of usage of one letter variables in MDL
code since it makes code harder to search in (according
to reviewer).
------------------------------------------------------------
revno: 2630.4.16
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Thu 2008-05-29 09:45:02 +0400
message:
WL#3726 "DDL locking for all metadata objects".
After review changes in progress.
Tweaked some comments and did some renames to
avoid ambiguites.
sql/mysql_priv.h:
Removed name_lock_locked_table() function.
sql/sql_base.cc:
Got rid of name_lock_locked_table() function after replacing
the only call to it with its body.
Simplified open_table() code by making "action" argument
mandatory (i.e. one now should always pass non-0 pointer
in this argument).
Renamed TABLE_LIST::open_table_type to open_type to
avoid confusing it with type of table.
Adjusted comments according to review.
sql/sql_handler.cc:
Added comment clarifying in which cases we can have TABLE::mdl_lock
set to 0.
sql/sql_insert.cc:
Now the 4th argument of open_table() is mandatory (it makes
no sense to complicate open_table() code when we can simply
pass dummy variable).
sql/sql_parse.cc:
Renamed TABLE_LIST::open_table_type to open_type to
avoid confusing it with type of table.
sql/sql_prepare.cc:
Renamed TABLE_LIST::open_table_type to open_type to
avoid confusing it with type of table.
sql/sql_table.cc:
Now the 4th argument of open_table() is mandatory (it makes
no sense to complicate open_table() code when we can simply
pass dummy variable).
sql/sql_trigger.cc:
Replaced the only call to name_lock_locked_table() function
with its body.
sql/sql_view.cc:
Renamed TABLE_LIST::open_table_type to open_type to
avoid confusing it with type of table.
sql/table.h:
Renamed TABLE_LIST::open_table_type to open_type (to
avoid confusing it with type of table) and improved
comments describing this member.
------------------------------------------------------------
revno: 2630.4.14
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Wed 2008-05-28 12:16:03 +0400
message:
WL#3726 "DDL locking for all metadata objects".
After review fixes in progress. Removed unused code and
adjusted names of functions/methods to better reflect
their current function.
sql/mysql_priv.h:
Changed names of close_data_files_and_morph_locks() and
close_handle_and_leave_table_as_lock() to better reflect
their current function (locking is now responsibility
of metadata locking subsystem).
sql/sql_base.cc:
Changed names of close_data_files_and_morph_locks() and
close_handle_and_leave_table_as_lock() to better reflect
their current function (locking is now responsibility
of metadata locking subsystem). Also adjusted comments
describing these functions.
Got rid of TABLE::open_placeholder since it is no longer
used (its value is never read anywhere).
TABLE::needs_reopen_or_name_lock() was renamed to needs_reopen()
since we no longer use name-locks
sql/sql_handler.cc:
TABLE::needs_reopen_or_name_lock() was renamed to needs_reopen()
since we no longer use name-locks.
sql/sql_insert.cc:
TABLE::needs_reopen_or_name_lock() was renamed to needs_reopen()
since we no longer use name-locks
sql/sql_partition.cc:
Changed name of close_data_files_and_morph_locks() to
better reflect its current function (locking is now
responsibility of metadata locking subsystem).
sql/sql_table.cc:
Changed names of close_data_files_and_morph_locks() and
close_handle_and_leave_table_as_lock() to better reflect
their current function (locking is now responsibility
of metadata locking subsystem).
Got rid of TABLE::open_placeholder since it is no longer
used.
sql/sql_trigger.cc:
Changed name of close_data_files_and_morph_locks() to
better reflect its current function (locking is now
responsibility of metadata locking subsystem).
sql/table.h:
Got rid of TABLE::open_placeholder which is no longer used
altough its value was set in several places no code reads it).
Removed unused TABLE::is_name_opened() method.
Finally TABLE::needs_reopen_or_name_lock() was renamed to
needs_reopen() since we no longer use name-locks.
-------------------------------------------------------------------
revno: 2630.6.6
committer: Konstantin Osipov <konstantin@mysql.com>
branch nick: mysql-6.0-3726
timestamp: Tue 2008-05-27 16:15:44 +0400
message:
Implement code review fixes for WL#3726 "DDL locking for all
metadata objects": cleanup the code from share->mutex
acquisitions, which are now obsolete.
sql/ha_partition.cc:
Rename share->mutex to share->LOCK_ha_data. The mutex never
protected the entire share. The right way to protect a share
is to acquire an MDL lock.
sql/ha_partition.h:
Rename share->mutex to share->LOCK_ha_data.
sql/sql_base.cc:
Remove LOCK_table_share. Do not acquire share->mutex when
deleting a table share or incrementing its ref_count.
All these operations are and must continue to be protected by LOCK_open
and respective MDL locks.
sql/sql_view.cc:
Remove acquisition of share->mutex when incrementing share->ref_count.
sql/table.cc:
Simplify release_table_shar() by removing dead code related
to share->mutex from it.
sql/table.h:
Rename TABLE_SHARE::mutex to TABLE_SHARE::LOCK_ha_data
to better reflect its purpose.
storage/myisam/ha_myisam.cc:
Rename share->mutex to share->LOCK_ha_data.
------------------------------------------------------------
revno: 2630.6.1
committer: Konstantin Osipov <konstantin@mysql.com>
branch nick: mysql-6.0-3726
timestamp: Tue 2008-05-27 13:45:34 +0400
message:
Remove an unused argument from release_table_share().
Remove unused members from TABLE_SHARE struct.
Review comments in scope of WL#3726 "DDL locking for all metadata
objects"
sql/mysql_priv.h:
Update declaration.
sql/sql_base.cc:
Upate declaration and the comment (release_share()).
sql/sql_plist.h:
A cosmetic change, is_empty() is a const method.
sql/sql_table.cc:
Update to use the new declaration of release_table_share().
sql/sql_view.cc:
Update to use the new declaration of release_table_share().
sql/table.cc:
Update to use the new declaration of release_table_share().
Remove dead code.
sql/table.h:
Remove unused members of TABLE.
Backport of:
------------------------------------------------------------
revno: 2630.4.1
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Fri 2008-05-23 17:54:03 +0400
message:
WL#3726 "DDL locking for all metadata objects".
After review fixes in progress.
------------------------------------------------------------
This is the first patch in series. It transforms the metadata
locking subsystem to use a dedicated module (mdl.h,cc). No
significant changes in the locking protocol.
The import passes the test suite with the exception of
deprecated/removed 6.0 features, and MERGE tables. The latter
are subject to a fix by WL#4144.
Unfortunately, the original changeset comments got lost in a merge,
thus this import has its own (largely insufficient) comments.
This patch fixes Bug#25144 "replication / binlog with view breaks".
Warning: this patch introduces an incompatible change:
Under LOCK TABLES, it's no longer possible to FLUSH a table that
was not locked for WRITE.
Under LOCK TABLES, it's no longer possible to DROP a table or
VIEW that was not locked for WRITE.
******
Backport of:
------------------------------------------------------------
revno: 2630.4.2
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Sat 2008-05-24 14:03:45 +0400
message:
WL#3726 "DDL locking for all metadata objects".
After review fixes in progress.
******
Backport of:
------------------------------------------------------------
revno: 2630.4.3
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Sat 2008-05-24 14:08:51 +0400
message:
WL#3726 "DDL locking for all metadata objects"
Fixed failing Windows builds by adding mdl.cc to the lists
of files needed to build server/libmysqld on Windows.
******
Backport of:
------------------------------------------------------------
revno: 2630.4.4
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Sat 2008-05-24 21:57:58 +0400
message:
WL#3726 "DDL locking for all metadata objects".
Fix for assert failures in kill.test which occured when one
tried to kill ALTER TABLE statement on merge table while it
was waiting in wait_while_table_is_used() for other connections
to close this table.
These assert failures stemmed from the fact that cleanup code
in this case assumed that temporary table representing new
version of table was open with adding to THD::temporary_tables
list while code which were opening this temporary table wasn't
always fulfilling this.
This patch changes code that opens new version of table to
always do this linking in. It also streamlines cleanup process
for cases when error occurs while we have new version of table
open.
******
WL#3726 "DDL locking for all metadata objects"
Add libmysqld/mdl.cc to .bzrignore.
******
Backport of:
------------------------------------------------------------
revno: 2630.4.6
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Sun 2008-05-25 00:33:22 +0400
message:
WL#3726 "DDL locking for all metadata objects".
Addition to the fix of assert failures in kill.test caused by
changes for this worklog.
Make sure we close the new table only once.
.bzrignore:
Add libmysqld/mdl.cc
libmysqld/CMakeLists.txt:
Added mdl.cc to the list of files needed for building of libmysqld.
libmysqld/Makefile.am:
Added files implementing new meta-data locking subsystem to the server.
mysql-test/include/handler.inc:
Use separate connection for waiting while threads performing DDL
operations conflicting with open HANDLER tables reach blocked
state. This is required because now we check and close tables open
by HANDLER statements in this connection conflicting with DDL in
another each time open_tables() is called and thus select from I_S
which is used for waiting will unblock DDL operations if issued
from connection with open HANDLERs.
mysql-test/r/create.result:
Adjusted test case after change in implementation of CREATE TABLE
... SELECT. We no longer have special check in open_table() which
catches the case when we select from the table created. Instead we
rely on unique_table() call which happens after opening and
locking all tables.
mysql-test/r/flush.result:
FLUSH TABLES WITH READ LOCK can no longer happen under LOCK
TABLES. Updated test accordingly.
mysql-test/r/flush_table.result:
Under LOCK TABLES we no longer allow to do FLUSH TABLES for tables
locked for read. Updated test accordingly.
mysql-test/r/handler_innodb.result:
Use separate connection for waiting while threads performing DDL
operations conflicting with open HANDLER tables reach blocked
state. This is required because now we check and close tables open
by HANDLER statements in this connection conflicting with DDL in
another each time open_tables() is called and thus select from I_S
which is used for waiting will unblock DDL operations if issued
from connection with open HANDLERs.
mysql-test/r/handler_myisam.result:
Use separate connection for waiting while threads performing DDL
operations conflicting with open HANDLER tables reach blocked
state. This is required because now we check and close tables open
by HANDLER statements in this connection conflicting with DDL in
another each time open_tables() is called and thus select from I_S
which is used for waiting will unblock DDL operations if issued
from connection with open HANDLERs.
mysql-test/r/information_schema.result:
Additional test for WL#3726 "DDL locking for all metadata
objects". Check that we use high-priority metadata lock requests
when filling I_S tables.
Rearrange tests to match 6.0 better (fewer merge conflicts).
mysql-test/r/kill.result:
Added tests checking that DDL and DML statements waiting for
metadata locks can be interrupted by KILL command.
mysql-test/r/lock.result:
One no longer is allowed to do DROP VIEW under LOCK TABLES even if
this view is locked by LOCK TABLES. The problem is that in such
situation write locks on view are not mutually exclusive so
upgrading metadata lock which is required for dropping of view
will lead to deadlock.
mysql-test/r/partition_column_prune.result:
Update results (same results in 6.0), WL#3726
mysql-test/r/partition_pruning.result:
Update results (same results in 6.0), WL#3726
mysql-test/r/ps_ddl.result:
We no longer invalidate prepared CREATE TABLE ... SELECT statement
if target table changes. This is OK since it is not strictly
necessary.
The first change is wrong, is caused by FLUSH TABLE
now flushing all unused tables. This is a regression that
Dmitri fixed in 6.0 in a follow up patch.
mysql-test/r/sp.result:
Under LOCK TABLES we no longer allow accessing views which were
not explicitly locked. To access view we need to obtain metadata
lock on it and doing this under LOCK TABLES may lead to deadlocks.
mysql-test/r/view.result:
One no longer is allowed to do DROP VIEW under LOCK TABLES even if
this view is locked by LOCK TABLES. The problem is that in such
situation even "write locks" on view are not mutually exclusive so
upgrading metadata lock which is required for dropping of view
will lead to deadlock
mysql-test/r/view_grant.result:
ALTER VIEW implementation was changed to open a view only after
checking that user which does alter has appropriate privileges on
it. This means that in case when user's privileges are
insufficient for this we won't check that new view definer is the
same as original one or user performing alter has SUPER privilege.
Adjusted test case accordingly.
mysql-test/r/view_multi.result:
Added test case for bug#25144 "replication / binlog with view
breaks".
mysql-test/suite/rpl/t/disabled.def:
Disable test for deprecated features (they don't work with new MDL).
mysql-test/t/create.test:
Adjusted test case after change in implementation of CREATE TABLE
... SELECT. We no longer have special check in open_table() which
catches the case when we select from the table created. Instead we
rely on unique_table() call which happens after opening and
locking all tables.
mysql-test/t/disabled.def:
Disable merge.test, subject of WL#4144
mysql-test/t/flush.test:
FLUSH TABLES WITH READ LOCK can no longer happen under LOCK
TABLES. Updated test accordingly.
mysql-test/t/flush_table.test:
Under LOCK TABLES we no longer allow to do FLUSH TABLES for tables
locked for read. Updated test accordingly.
mysql-test/t/information_schema.test:
Additional test for WL#3726 "DDL locking for all metadata
objects". Check that we use high-priority metadata lock requests
when filling I_S tables.
Rearrange the results for easier merges with 6.0.
mysql-test/t/kill.test:
Added tests checking that DDL and DML statements waiting for
metadata locks can be interrupted by KILL command.
mysql-test/t/lock.test:
One no longer is allowed to do DROP VIEW under LOCK TABLES even if
this view is locked by LOCK TABLES. The problem is that in such
situation write locks on view are not mutually exclusive so
upgrading metadata lock which is required for dropping of view
will lead to deadlock.
mysql-test/t/lock_multi.test:
Adjusted test case to the changes of status in various places
caused by change in implementation FLUSH TABLES WITH READ LOCK,
which is now takes global metadata lock before flushing tables and
therefore waits on at these places.
mysql-test/t/ps_ddl.test:
We no longer invalidate prepared CREATE TABLE ... SELECT statement
if target table changes. This is OK since it is not strictly
necessary.
The first change is wrong, is caused by FLUSH TABLE
now flushing all unused tables. This is a regression that
Dmitri fixed in 6.0 in a follow up patch.
mysql-test/t/sp.test:
Under LOCK TABLES we no longer allow accessing views which were
not explicitly locked. To access view we need to obtain metadata
lock on it and doing this under LOCK TABLES may lead to deadlocks.
mysql-test/t/trigger_notembedded.test:
Adjusted test case to the changes of status in various places
caused by change in implementation FLUSH TABLES WITH READ LOCK,
which is now takes global metadata lock before flushing tables and
therefore waits on at these places.
mysql-test/t/view.test:
One no longer is allowed to do DROP VIEW under LOCK TABLES even if
this view is locked by LOCK TABLES. The problem is that in such
situation even "write locks" on view are not mutually exclusive so
upgrading metadata lock which is required for dropping of view
will lead to deadlock.
mysql-test/t/view_grant.test:
ALTER VIEW implementation was changed to open a view only after
checking that user which does alter has appropriate privileges on
it. This means that in case when user's privileges are
insufficient for this we won't check that new view definer is the
same as original one or user performing alter has SUPER privilege.
Adjusted test case accordingly.
mysql-test/t/view_multi.test:
Added test case for bug#25144 "replication / binlog with view
breaks".
sql/CMakeLists.txt:
Added mdl.cc to the list of files needed for building of server.
sql/Makefile.am:
Added files implementing new meta-data locking subsystem to the
server.
sql/event_db_repository.cc:
Allocate metadata lock requests objects (MDL_LOCK) on execution
memory root in cases when TABLE_LIST objects is also allocated
there or on stack.
sql/ha_ndbcluster.cc:
Adjusted code to work nicely with new metadata locking subsystem.
close_cached_tables() no longer has wait_for_placeholder argument.
Instead of relying on this parameter and related behavior FLUSH
TABLES WITH READ LOCK now takes global shared metadata lock.
sql/ha_ndbcluster_binlog.cc:
Adjusted code to work with new metadata locking subsystem.
close_cached_tables() no longer has wait_for_placeholder argument.
Instead of relying on this parameter and related behavior FLUSH
TABLES WITH READ LOCK now takes global shared metadata lock.
sql/handler.cc:
update_frm_version():
Directly update TABLE_SHARE::mysql_version member instead of
going through all TABLE instances for this table (old code was a
legacy from pre-table-definition-cache days).
sql/lock.cc:
Use new metadata locking subsystem. Threw away most of functions
related to name locking as now one is supposed to use metadata
locking API instead. In lock_global_read_lock() and
unlock_global_read_lock() in order to avoid problems with global
read lock sneaking in at the moment when we perform FLUSH TABLES
or ALTER TABLE under LOCK TABLES and when tables being reopened
are protected only by metadata locks we also have to take global
shared meta data lock.
sql/log_event.cc:
Adjusted code to work with new metadata locking subsystem. For
tables open by slave thread for applying RBR events allocate
memory for lock request object in the same chunk of memory as
TABLE_LIST objects for them. In order to ensure that we keep these
objects around until tables are open always close tables before
calling Relay_log_info::clear_tables_to_lock(). Use new auxiliary
Relay_log_info::slave_close_thread_tables() method to enforce
this.
sql/log_event_old.cc:
Adjusted code to work with new metadata locking subsystem. Since
for tables open by slave thread for applying RBR events memory for
lock request object is allocated in the same chunk of memory as
TABLE_LIST objects for them we have to ensure that we keep these
objects around until tables are open. To ensure this we always
close tables before calling
Relay_log_info::clear_tables_to_lock(). To enfore this we use
new auxiliary Relay_log_info::slave_close_thread_tables()
method.
sql/mdl.cc:
Implemented new metadata locking subsystem and API described in
WL3726 "DDL locking for all metadata objects".
sql/mdl.h:
Implemented new metadata locking subsystem and API described in
WL3726 "DDL locking for all metadata objects".
sql/mysql_priv.h:
- close_thread_tables()/close_tables_for_reopen() now has one more
argument which indicates that metadata locks should be released
but not removed from the context in order to be used later in
mdl_wait_for_locks() and tdc_wait_for_old_version().
- close_cached_table() routine is no longer public.
- Thread waiting in wait_while_table_is_used() can be now killed
so this function returns boolean to make caller aware of such
situation.
- We no longer have table cache as separate entity instead used
and unused TABLE instances are linked to TABLE_SHARE objects in
table definition cache.
- Now third argument of open_table() is also used for requesting
table repair or auto-discovery of table's new definition. So its
type was changed from bool to enum.
- Added tdc_open_view() function for opening view by getting its
definition from disk (and table cache in future).
- reopen_name_locked_table() no longer needs "link_in" argument as
now we have exclusive metadata locks instead of dummy TABLE
instances when this function is called.
- find_locked_table() now takes head of list of TABLE instances
instead of always scanning through THD::open_tables list. Also
added find_write_locked_table() auxiliary.
- reopen_tables(), close_cached_tables() no longer have
mark_share_as_old and wait_for_placeholder arguments. Instead of
relying on this parameters and related behavior FLUSH TABLES
WITH READ LOCK now takes global shared metadata lock.
- We no longer need drop_locked_tables() and
abort_locked_tables().
- mysql_ha_rm_tables() now always assume that LOCK_open is not
acquired by caller.
- Added notify_thread_having_shared_lock() callback invoked by
metadata locking subsystem when acquiring an exclusive lock, for
each thread that has a conflicting shared metadata lock.
- Introduced expel_table_from_cache() as replacement for
remove_table_from_cache() (the main difference is that this new
function assumes that caller follows metadata locking protocol
and never waits).
- Threw away most of functions related to name locking. One should
use new metadata locking subsystem and API instead.
sql/mysqld.cc:
Got rid of call initializing/deinitializing table cache since now
it is embedded into table definition cache. Added calls for
initializing/ deinitializing metadata locking subsystem.
sql/rpl_rli.cc:
Introduced auxiliary Relay_log_info::slave_close_thread_tables()
method which is used for enforcing that we always close tables
open for RBR before deallocating TABLE_LIST elements and MDL_LOCK
objects for them.
sql/rpl_rli.h:
Introduced auxiliary Relay_log_info::slave_close_thread_tables()
method which is used for enforcing that we always close tables
open for RBR before deallocating TABLE_LIST elements and MDL_LOCK
objects for them.
sql/set_var.cc:
close_cached_tables() no longer has wait_for_placeholder argument.
Instead of relying on this parameter and related behavior FLUSH
TABLES WITH READ LOCK now takes global shared metadata lock.
sql/sp_head.cc:
For tables added to the statement's table list by prelocking
algorithm we allocate these objects either on the same memory as
corresponding table list elements or on THD::locked_tables_root
(if we are building table list for LOCK TABLES).
sql/sql_acl.cc:
Allocate metadata lock requests objects (MDL_LOCK) on execution
memory root in cases when we use stack TABLE_LIST objects to open
tables. Got rid of redundant code by using unlock_locked_tables()
function.
sql/sql_base.cc:
Changed code to use new MDL subsystem. Got rid of separate table
cache. Now used and unused TABLE instances are linked to the
TABLE_SHAREs in table definition cache.
check_unused():
Adjusted code to the fact that we no longer have separate table
cache. Removed dead code.
table_def_free():
Free TABLE instances referenced from TABLE_SHARE objects before
destroying table definition cache.
get_table_share():
Added assert which ensures that noone will be able to access
table (and its share) without acquiring some kind of metadata
lock first.
close_handle_and_leave_table_as_lock():
Adjusted code to the fact that TABLE instances now are linked to
list in TABLE_SHARE.
list_open_tables():
Changed this function to use table definition cache instead of
table cache.
free_cache_entry():
Unlink freed TABLE elements from the list of all TABLE instances
for the table in TABLE_SHARE.
kill_delayed_thread_for_table():
Added auxiliary for killing delayed insert threads for
particular table.
close_cached_tables():
Got rid of wait_for_refresh argument as we now rely on global
shared metadata lock to prevent FLUSH WITH READ LOCK sneaking in
when we are reopening tables. Heavily reworked this function to
use new MDL code and not to rely on separate table cache entity.
close_open_tables():
We no longer have separate table cache.
close_thread_tables():
Release metadata locks after closing all tables. Added skip_mdl
argument which allows us not to remove metadata lock requests
from the context in case when we are going to use this requests
later in mdl_wait_for_locks() and tdc_wait_for_old_versions().
close_thread_table()/close_table_for_reopen():
Since we no longer have separate table cache and all TABLE
instances are linked to TABLE_SHARE objects in table definition
cache we have to link/unlink TABLE object to/from appropriate
lists in the share.
name_lock_locked_table():
Moved redundant code to find_write_locked_table() function and
adjusted code to the fact that wait_while_table_is_used() can
now return with an error if our thread is killed.
reopen_table_entry():
We no longer need "link_in" argument as with MDL we no longer
call this function with dummy TABLE object pre-allocated and
added to the THD::open_tables. Also now we add newly-open TABLE
instance to the list of share's used TABLE instances.
table_cache_insert_placeholder():
Got rid of name-locking legacy.
lock_table_name_if_not_cached():
Moved to sql_table.cc the only place where it is used. It was
also reimplemented using new MDL API.
open_table():
- Reworked this function to use new MDL subsystem.
- Changed code to deal with table definition cache directly
instead of going through separate table cache.
- Now third argument is also used for requesting table repair
or auto-discovery of table's new definition. So its type was
changed from bool to enum.
find_locked_table()/find_write_locked_table():
Accept head of list of TABLE objects as first argument and use
this list instead of always searching in THD::open_tables list.
Also added auxiliary for finding write-locked locked tables.
reopen_table():
Adjusted function to work with new MDL subsystem and to properly
manuipulate with lists of used/unused TABLE instaces in
TABLE_SHARE.
reopen_tables():
Removed mark_share_as_old parameter. Instead of relying on it
and related behavior FLUSH TABLES WITH READ LOCK now takes
global shared metadata lock. Changed code after removing
separate table cache.
drop_locked_tables()/abort_locked_tables():
Got rid of functions which are no longer needed.
unlock_locked_tables():
Moved this function from sql_parse.cc and changed it to release
memory which was used for allocating metadata lock requests for
tables open and locked by LOCK TABLES.
tdc_open_view():
Intoduced function for opening a view by getting its definition
from disk (and table cache in future).
reopen_table_entry():
Introduced function for opening table definitions while holding
exclusive metatadata lock on it.
open_unireg_entry():
Got rid of this function. Most of its functionality is relocated
to open_table() and open_table_fini() functions, and some of it
to reopen_table_entry() and tdc_open_view(). Also code
resposible for auto-repair and auto-discovery of tables was
moved to separate function.
open_table_entry_fini():
Introduced function which contains common actions which finalize
process of TABLE object creation.
auto_repair_table():
Moved code responsible for auto-repair of table being opened
here.
handle_failed_open_table_attempt()
Moved code responsible for handling failing attempt to open
table to one place (retry due to lock conflict/old version,
auto-discovery and repair).
open_tables():
- Flush open HANDLER tables if they have old version of if there
is conflicting metadata lock against them (before this moment
we had this code in open_table()).
- When we open view which should be processed via derived table
on the second execution of prepared statement or stored
routine we still should call open_table() for it in order to
obtain metadata lock on it and prepare its security context.
- In cases when we discover that some special handling of
failure to open table is needed call
handle_failed_open_table_attempt() which handles all such
scenarios.
open_ltable():
Handling of various special scenarios of failure to open a table
was moved to separate handle_failed_open_table_attempt()
function.
remove_db_from_cache():
Removed this function as it is no longer used.
notify_thread_having_shared_lock():
Added callback which is invoked by MDL subsystem when acquiring
an exclusive lock, for each thread that has a conflicting shared
metadata lock.
expel_table_from_cache():
Introduced function for removing unused TABLE instances. Unlike
remove_table_from_cache() it relies on caller following MDL
protocol and having appropriate locks when calling it and thus
does not do any waiting if table is still in use.
tdc_wait_for_old_version():
Added function which allows open_tables() to wait in cases when
we discover that we should back-off due to presence of old
version of table.
abort_and_upgrade_lock():
Use new MDL calls.
mysql_wait_completed_table():
Got rid of unused function.
open_system_tables_for_read/for_update()/performance_schema_table():
Allocate MDL_LOCK objects on execution memory root in cases when
TABLE_LIST objects for corresponding tables is allocated on
stack.
close_performance_schema_table():
Release metadata locks after closing tables.
******
Use I_P_List for free/used tables list in the table share.
sql/sql_binlog.cc:
Use Relay_log_info::slave_close_thread_tables() method to enforce
that we always close tables open for RBR before deallocating
TABLE_LIST elements and MDL_LOCK objects for them.
sql/sql_class.cc:
Added meta-data locking contexts as part of Open_tables_state
context. Also introduced THD::locked_tables_root memory root
which is to be used for allocating MDL_LOCK objects for tables in
LOCK TABLES statement (end of lifetime for such objects is UNLOCK
TABLES so we can't use statement or execution root for them).
sql/sql_class.h:
Added meta-data locking contexts as part of Open_tables_state
context. Also introduced THD::locked_tables_root memory root
which is to be used for allocating MDL_LOCK objects for tables in
LOCK TABLES statement (end of lifetime for such objects is UNLOCK
TABLES so we can't use statement or execution root for them).
Note: handler_mdl_context and locked_tables_root and
mdl_el_root will be removed by subsequent patches.
sql/sql_db.cc:
mysql_rm_db() does not really need to call remove_db_from_cache()
as it drops each table in the database using
mysql_rm_table_part2(), which performs all necessary operations on
table (definition) cache.
sql/sql_delete.cc:
Use the new metadata locking API for TRUNCATE.
sql/sql_handler.cc:
Changed HANDLER implementation to use new metadata locking
subsystem. Note that MDL_LOCK objects for HANDLER tables are
allocated in the same chunk of heap memory as TABLE_LIST object
for those tables.
sql/sql_insert.cc:
mysql_insert():
find_locked_table() now takes head of list of TABLE object as
its argument instead of always scanning through THD::open_tables
list.
handle_delayed_insert():
Allocate metadata lock request object for table open by delayed
insert thread on execution memroot. create_table_from_items():
We no longer allocate dummy TABLE objects for tables being
created if they don't exist. As consequence
reopen_name_locked_table() no longer has link_in argument.
open_table() now has one more argument which is not relevant for
temporary tables.
sql/sql_parse.cc:
- Moved unlock_locked_tables() routine to sql_base.cc and made
available it in other files. Got rid of some redundant code by
using this function.
- Replaced boolean TABLE_LIST::create member with enum
open_table_type member.
- Use special memory root for allocating MDL_LOCK objects for
tables open and locked by LOCK TABLES (these object should live
till UNLOCK TABLES so we can't allocate them on statement nor
execution memory root). Also properly set metadata lock
upgradability attribure for those tables.
- Under LOCK TABLES it is no longer allowed to flush tables which
are not write-locked as this breaks metadata locking protocol
and thus potentially might lead to deadlock.
- Added auxiliary adjust_mdl_locks_upgradability() function.
sql/sql_partition.cc:
Adjusted code to the fact that reopen_tables() no longer has
"mark_share_as_old" argument. Got rid of comments which are no
longer true.
sql/sql_plist.h:
Added I_P_List template class for parametrized intrusive doubly
linked lists and I_P_List_iterator for corresponding iterator.
Unlike for I_List<> list elements of such list can participate in
several lists. Unlike List<> such lists are doubly-linked and
intrusive.
sql/sql_plugin.cc:
Allocate metadata lock requests objects (MDL_LOCK) on execution
memory root in cases when we use stack TABLE_LIST objects to open
tables.
sql/sql_prepare.cc:
Replaced boolean TABLE_LIST::create member with enum
open_table_type member. This allows easily handle situation in
which instead of opening the table we want only to take exclusive
metadata lock on it.
sql/sql_rename.cc:
Use new metadata locking subsystem in implementation of RENAME
TABLE.
sql/sql_servers.cc:
Allocate metadata lock requests objects (MDL_LOCK) on execution
memory root in cases when we use stack TABLE_LIST objects to open
tables. Got rid of redundant code by using unlock_locked_tables()
function.
sql/sql_show.cc:
Acquire shared metadata lock when we are getting information for
I_S table directly from TABLE_SHARE without doing full-blown table
open. We use high priority lock request in this situation in
order to avoid deadlocks.
Also allocate metadata lock requests objects (MDL_LOCK) on
execution memory root in cases when TABLE_LIST objects are also
allocated there
sql/sql_table.cc:
mysql_rm_table():
Removed comment which is no longer relevant.
mysql_rm_table_part2():
Now caller of mysql_ha_rm_tables() should not own LOCK_open.
Adjusted code to use new metadata locking subsystem instead of
name-locks.
lock_table_name_if_not_cached():
Moved this function from sql_base.cc to this file and
reimplemented it using metadata locking API.
mysql_create_table():
Adjusted code to use new MDL API.
wait_while_table_is_used():
Changed function to use new MDL subsystem. Made thread waiting
in it killable (this also led to introduction of return value so
caller can distinguish successful executions from situations
when waiting was aborted).
close_cached_tables():
Thread waiting in this function is killable now. As result it
has return value for distinguishing between succes and failure.
Got rid of redundant boradcast_refresh() call.
prepare_for_repair():
Use MDL subsystem instead of name-locks.
mysql_admin_table():
mysql_ha_rm_tables() now always assumes that caller doesn't own
LOCK_open.
mysql_repair_table():
We should mark all elements of table list as requiring
upgradable metadata locks.
mysql_create_table_like():
Use new MDL subsystem instead of name-locks.
create_temporary_tables():
We don't need to obtain metadata locks when creating temporary
table.
mysql_fast_or_online_alter_table():
Thread waiting in wait_while_table_is_used() is now killable.
mysql_alter_table():
Adjusted code to work with new MDL subsystem and to the fact
that threads waiting in what_while_table_is_used() and
close_cached_table() are now killable.
sql/sql_test.cc:
We no longer have separate table cache. TABLE instances are now
associated with/linked to TABLE_SHARE objects in table definition
cache.
sql/sql_trigger.cc:
Adjusted code to work with new metadata locking subsystem. Also
reopen_tables() no longer has mark_share_as_old argument (Instead
of relying on this parameter and related behavior FLUSH TABLES
WITH READ LOCK now takes global shared metadata lock).
sql/sql_udf.cc:
Allocate metadata lock requests objects (MDL_LOCK) on execution
memory root in cases when we use stack TABLE_LIST objects to open
tables.
sql/sql_update.cc:
Adjusted code to work with new meta-data locking subsystem.
sql/sql_view.cc:
Added proper meta-data locking to implementations of
CREATE/ALTER/DROP VIEW statements. Now we obtain exclusive
meta-data lock on a view before creating/ changing/dropping it.
This ensures that all concurrent statements that use this view
will finish before our statement will proceed and therefore we
will get correct order of statements in the binary log.
Also ensure that TABLE_LIST::mdl_upgradable attribute is properly
propagated for underlying tables of view.
sql/table.cc:
Added auxiliary alloc_mdl_locks() function for allocating metadata
lock request objects for all elements of table list.
sql/table.h:
TABLE_SHARE:
Got rid of unused members. Introduced members for storing lists
of used and unused TABLE objects for this share.
TABLE:
Added members for linking TABLE objects into per-share lists of
used and unused TABLE instances. Added member for holding
pointer to metadata lock for this table.
TABLE_LIST:
Replaced boolean TABLE_LIST::create member with enum
open_table_type member. This allows easily handle situation in
which instead of opening the table we want only to take
exclusive meta-data lock on it (we need this in order to handle
ALTER VIEW and CREATE VIEW statements).
Introduced new mdl_upgradable member for marking elements of
table list for which we need to take upgradable shared metadata
lock instead of plain shared metadata lock. Added pointer for
holding pointer to MDL_LOCK for the table.
Added auxiliary alloc_mdl_locks() function for allocating metadata
lock requests objects for all elements of table list. Added
auxiliary set_all_mdl_upgradable() function for marking all
elements in table list as requiring upgradable metadata locks.
storage/myisammrg/ha_myisammrg.cc:
Allocate MDL_LOCK objects for underlying tables of MERGE table.
To be reworked once Ingo pushes his patch for WL4144.
------------------------------------------------------------
revno: 2572.2.1
revision-id: sp1r-davi@mysql.com/endora.local-20080227225948-16317
parent: sp1r-anozdrin/alik@quad.-20080226165712-10409
committer: davi@mysql.com/endora.local
timestamp: Wed 2008-02-27 19:59:48 -0300
message:
Bug#27525 table not found when using multi-table-deletes with aliases over several databas
Bug#30234 Unexpected behavior using DELETE with AS and USING
The multi-delete statement has a documented limitation that
cross-database multiple-table deletes using aliases are not
supported because it fails to find the tables by alias if it
belongs to a different database. The problem is that when
building the list of tables to delete from, if a database
name is not specified (maybe an alias) it defaults to the
name of the current selected database, making impossible to
to properly resolve tables by alias later. Another problem
is a inconsistency of the multiple table delete syntax that
permits ambiguities in a delete statement (aliases that refer
to multiple different tables or vice-versa).
The first step for a solution and proper implementation of
the cross-databse multiple table delete is to get rid of any
ambiguities in a multiple table statement. Currently, the parser
is accepting multiple table delete statements that have no obvious
meaning, such as:
DELETE a1 FROM db1.t1 AS a1, db2.t2 AS a1;
DELETE a1 AS a1 FROM db1.t1 AS a1, db2.t2 AS a1;
The solution is to resolve the left part of a delete statement
using the right part, if the a table on right has an alias,
it must be referenced in the left using the given alias. Also,
each table on the left side must match unambiguously only one
table in the right side.
mysql-test/r/delete.result:
Add test case result for Bug#27525 and Bug#21148
mysql-test/r/derived.result:
Update error.
mysql-test/suite/rpl/r/rpl_multi_delete2.result:
Update syntax.
mysql-test/suite/rpl/t/rpl_multi_delete2.test:
Update syntax.
mysql-test/t/delete.test:
Add test case for Bug#27525 and Bug#21148
mysql-test/t/derived.test:
Update statement error, alias is properly resolved now.
sql/sql_parse.cc:
Implement new algorithm for the resolution of alias in
a multiple table delete statement.
sql/sql_yacc.yy:
Rework multi-delete parser rules to not accept table alias
for the table source list.
sql/table.h:
Add flag to signal that the table has a alias set or
that fully qualified table name was given.
Conflicts
=========
Text conflict in .bzr-mysql/default.conf
Text conflict in libmysqld/CMakeLists.txt
Text conflict in libmysqld/Makefile.am
Text conflict in mysql-test/collections/default.experimental
Text conflict in mysql-test/extra/rpl_tests/rpl_row_sp006.test
Text conflict in mysql-test/suite/binlog/r/binlog_tmp_table.result
Text conflict in mysql-test/suite/rpl/r/rpl_loaddata.result
Text conflict in mysql-test/suite/rpl/r/rpl_loaddata_fatal.result
Text conflict in mysql-test/suite/rpl/r/rpl_row_create_table.result
Text conflict in mysql-test/suite/rpl/r/rpl_row_sp006_InnoDB.result
Text conflict in mysql-test/suite/rpl/r/rpl_stm_log.result
Text conflict in mysql-test/suite/rpl_ndb/r/rpl_ndb_circular_simplex.result
Text conflict in mysql-test/suite/rpl_ndb/r/rpl_ndb_sp006.result
Text conflict in mysql-test/t/mysqlbinlog.test
Text conflict in sql/CMakeLists.txt
Text conflict in sql/Makefile.am
Text conflict in sql/log_event_old.cc
Text conflict in sql/rpl_rli.cc
Text conflict in sql/slave.cc
Text conflict in sql/sql_binlog.cc
Text conflict in sql/sql_lex.h
21 conflicts encountered.
NOTE
====
mysql-5.1-rpl-merge has been made a mirror of mysql-next-mr:
- "mysql-5.1-rpl-merge$ bzr pull ../mysql-next-mr"
This is the first cset (merge/...) committed after pulling
from mysql-next-mr.
EXPLAIN EXTENDED warning.
Query optimizer searches for the constant tables and optimizes them away. This
means that fields of such tables are substituted for their values and on later
phases they are treated as constants. After this constant tables are removed
from the query execution plan. Nevertheless constant tables were shown in
the EXPLAIN EXTENDED warning thus producing query that might be not an
equivalent of the original query.
Now the print_join function skips all tables that were optimized away from
printing to the EXPLAIN EXTENDED warning. If all tables were optimized away it
produces the 'FROM dual' clause.
mysql-test/r/explain.result:
A test case added for the bug#30302.
mysql-test/r/func_default.result:
Adjusted test case result after fix for the bug#30302.
mysql-test/r/func_regexp.result:
Adjusted test case result after fix for the bug#30302.
mysql-test/r/func_test.result:
Adjusted test case result after fix for the bug#30302.
mysql-test/r/having.result:
Adjusted test case result after fix for the bug#30302.
mysql-test/r/select.result:
Adjusted test case result after fix for the bug#30302.
mysql-test/r/subselect.result:
Adjusted test case result after fix for the bug#30302.
mysql-test/r/subselect3.result:
Adjusted test case result after fix for the bug#30302.
mysql-test/r/type_datetime.result:
Adjusted test case result after fix for the bug#30302.
mysql-test/t/explain.test:
A test case added for the bug#30302.
sql/sql_select.cc:
Bug#30302: Tables that were optimized away are printed in the
EXPLAIN EXTENDED warning.
Now the print_join function skips all tables that were optimized away from
printing to the EXPLAIN EXTENDED warning. If all tables were optimized away it
produces the 'FROM dual' clause.
sql/table.h:
Adjusted test case result after fix for the bug#30302.
The optimized_away flag is added to the TABLE_LIST struct.
get_table_share, drop_open_table
In the partition handler code, LOCK_open and share->LOCK_ha_data
are acquired in the wrong order in certain cases. When doing a
multi-row INSERT (i.e a INSERT..SELECT) in a table with auto-
increment column(s). the increments must be in a monotonically
continuous increasing sequence (i.e it can't have "holes"). To
achieve this, a lock is held for the duration of the operation.
share->LOCK_ha_data was used for this purpose.
Whenever there was a need to open a view _during_ the operation
(views are not currently pre-opened the way tables are), and
LOCK_open was grabbed, a deadlock could occur. share->LOCK_ha_data
is other places used _while_ holding LOCK_open.
A new mutex was introduced in the HA_DATA_PARTITION structure,
for exclusive use of the autoincrement data fields, so we don't
need to overload the use of LOCK_ha_data here.
A module test case has not been supplied, since the problem occurs
as a result of a race condition, and testing for this condition
is thus not deterministic. Testing for it could be done by
setting up a test case as described in the bug report.
----------------------------------------------------------
revno: 2630.22.8
committer: Konstantin Osipov <konstantin@mysql.com>
branch nick: mysql-6.0-runtime
timestamp: Sun 2008-08-10 18:49:52 +0400
message:
Get rid of typedef struct for the most commonly used types:
TABLE, TABLE_SHARE, LEX. This simplifies use of tags
and forward declarations.
buffering is used
FORCE INDEX FOR ORDER BY now prevents the optimizer from
using join buffering. As a result the optimizer can use
indexed access on the first table and doesn't need to
sort the complete resultset at the end of the statement.
view that has Group By
Table access rights checking function check_grant() assumed
that no view is opened when it's called.
This is not true with nested views where the inner view
needs materialization. In this case the view is already
materialized when check_grant() is called for it.
This caused check_grant() to not look for table level
grants on the materialized view table.
Fixed by checking if a view is already materialized and if
it is check table level grants using the original table name
(not the ones of the materialized temp table).
"CREATE TABLE TRANSACTIONAL PAGE_CHECKSUM ROW_FORMAT=PAGE accepted,
does nothing".
Put back stubs for members of structures that are shared between
sql/ and pluggable storage engines. to not break ABI unnecessarily.
To be NULL-merged into 5.4, where we do break the ABI already.
PAGE_CHECKSUM ROW_FORMAT=PAGE accepted, does nothing"
Remove unused code that would lead to warnings when compiling
sql_yacc.yy.
sql/handler.h:
Remove unused defines.
sql/sql_yacc.yy:
Remove unused grammar.
sql/table.h:
Remove unused TABLE members.
Problem 1:
When the 'Using index' optimization is used, the optimizer may still - after
cost-based optimization - decide to use another index in order to avoid using
a temporary table. But when this happens, the flag to the storage engine to
read index only (not table) was still set. Fixed by resetting the flag in the
storage engine and TABLE structure in the above scenario, unless the new index
allows for the same optimization.
Problem 2:
When a 'ref' access method was employed by cost-based optimizer, (when the column
is non-NULLable), it was assumed that it needed no initialization if 'quick' access
methods (since they are based on range scan). When ORDER BY optimization overrides
the decision, however, it expects to have this initialized and hence crashes.
Fixed in 5.1 (was fixed in 6.0 already) by initializing 'quick' even when there's
'ref' access.
mysql-test/r/order_by.result:
Bug#46454: Test result.
mysql-test/t/order_by.test:
Bug#46454: Test case.
sql/sql_select.cc:
Bug#46454:
Problem 1 fixed in make_join_select()
Problem 2 fixed in test_if_skip_sort_order()
sql/table.h:
Bug#46454: Added comment to field.
those keywords do nothing in 5.1 (they are meant for future versions, for example featuring the Maria engine)
so they are here removed from the syntax. Adding those keywords to future versions when needed is:
- WL#5034 "Add TRANSACTIONA=0|1 and PAGE_CHECKSUM=0|1 clauses to CREATE TABLE"
- WL#5037 "New ROW_FORMAT value for CREATE TABLE: PAGE"
mysql-test/r/create.result:
test that syntax is not accepted
mysql-test/t/create.test:
test that syntax is not accepted
sql/handler.cc:
remove ROW_FORMAT=PAGE
sql/handler.h:
Mark unused objects, but I don't remove them by fear of breaking any plugin which includes this file
(see also table.h)
sql/lex.h:
removing syntax
sql/sql_show.cc:
removing output of noise keywords in SHOW CREATE TABLE and INFORMATION_SCHEMA.TABLES
sql/sql_table.cc:
removing TRANSACTIONAL
sql/sql_yacc.yy:
removing syntax
sql/table.cc:
removing TRANSACTIONAL, PAGE_CHECKSUM. Their place in the frm file is not reclaimed,
for compatibility with older 5.1.
sql/table.h:
Mark unused objects, but I don't remove them by fear of breaking any plugin which includes this file
(and there are several engines which use the content TABLE_SHARE and thus rely on a certain binary
layout of this structure).
with gcc 4.3.2
Compiling MySQL with gcc 4.3.2 and later produces a number of
warnings, many of which are new with the recent compiler
versions.
This bug will be resolved in more than one patch to limit the
size of changesets. This is the second patch, fixing more
of the warnings.
Related to operator precedence and associativity.
Make the expressions as explicit as possible.
sql/field.h:
Silence gcc-4.3 warning: be more explicit.
sql/item.cc:
Silence gcc-4.3 warning: be more explicit.
sql/item_sum.cc:
Silence gcc-4.3 warning: be more explicit.
sql/log_event.cc:
Silence gcc-4.3 warning: be more explicit.
sql/spatial.h:
Silence gcc-4.3 warning: be more explicit.
sql/sql_lex.cc:
Silence gcc-4.3 warning: be more explicit.
sql/table.h:
Silence gcc-4.3 warning: be more explicit.
storage/federated/ha_federated.cc:
Fix operator precedence bug.
storage/heap/ha_heap.cc:
Silence gcc-4.3 warning: be more explicit.
Field_varstring::store
The code that temporary saved the bitmaps of the read set and the write set so that
it can set it to all columns for debug purposes was not expecting that the
table->read_set and table->write_set can be the same. And was always saving both in
sequence.
As a result the original value was never restored.
Fixed by saving & restoring the original value only once if the two sets are the
same (in a special set of functions).
mysql-test/r/select.result:
Bug #37936: test case
mysql-test/t/select.test:
Bug #37936: test case
sql/item_cmpfunc.cc:
Bug #37936: don't save/restore twice if the read and write sets are the same
sql/opt_range.cc:
Bug #37936: don't save/restore twice if the read and write sets are the same
sql/table.h:
Bug #37936: Make a designated set of functions that save/restore
both the read and the write sets in a single call.
sql_view.cc: required_view_parameters has been decreased by 2
(not by 1) because its value was incorrect: 16 instead of 15
(minor performance issue).
sql/sql_view.cc:
sql_view.cc: required_view_parameters has been decreased by 2
(not by 1) because its value was incorrect: 16 instead of 15
(minor performance issue).
missing after downgrade
Obsolete arc/ directory and view .frm file backup support
has been removed by the patch for bug 17823. However, that
bugfix caused a problem with "live downgrades" of the
server: if we rename some view 4 times under 5.1.29/5.0.72
and then try to rename it under 5.1.28/5.0.70 on the same
database, the server fails with a error:
query 'RENAME TABLE ... TO ...' failed: 6: Error on
delete of '....frm-0001' (Errcode: 2)
Also .frm file of that view may be lost (renamed to .frm~).
The server failed because it tried to rename latest 3
backup .frm files renaming the view: the server used an
integer value of the "revision" field of .frm file to
extract those file names. After the fix for bug 17823 those
files were not created/maintained any more, however the
"revision" field was incremented as usual. So, the server
failed renaming non existent files.
This fix solves the problem by removing the support for
"revision" .frm file field:
1. New server silently ignores existent "revision" fields
in old .frm files and never write it down;
2. Old server assumes, that missing "revision" field in new
.frm files means default value of 0.
3. Accordingly to the fix for bug 17823 the new server
drops arc/ directory on alter/rename view, so after
"live downgrade" old server begins maintenance of the
arc/ directory from scratch without conflicts with .frm
files.
sql/parse_file.cc:
Bug #40021: Renaming view fails, archived .frm for view is
missing after downgrade
1. static write_parameter(): the old_version parameter
and the section for FILE_OPTIONS_REV have been re moved.
2. write_parameter(): the max_versions parameter has been
removed;
3. sql_create_definition_file(): removal of dead code;
4. rename_in_schema_file(): revision and num_view_backups
parameters and dead code have been removed;
5. File_parser::parse(): FILE_OPTIONS_REV section has been
removed.
sql/parse_file.h:
Bug #40021: Renaming view fails, archived .frm for view is
missing after downgrade
1. The FILE_OPTIONS_REV constant has been removed.
2. sql_create_definition_file and rename_in_schema_file
functions: obsolete versions, revision and
num_view_backups parameters have been removed.
sql/sql_db.cc:
Bug #40021: Renaming view fails, archived .frm for view is
missing after downgrade
Commentary update.
sql/sql_trigger.cc:
Bug #40021: Renaming view fails, archived .frm for view is
missing after downgrade
sql_create_definition_file() calls have been updates to
new parameter lists.
sql/sql_view.cc:
Bug #40021: Renaming view fails, archived .frm for view is
missing after downgrade
1. The mysql_create_view function code is used for both
CREATE VIEW and ALTER queries, but query cache is
necessary for ALTER command only. Check for a non first
view revision has been replaced with a direct check for
ALTER query.
2. The num_view_backups global constant has been removed.
3. view_parameters: the "revision" .frm field support has
been removed.
4. sql_create_definition_file and rename_in_schema_file
function calls have been updates to new parameter lists.
sql/table.h:
Bug #40021: Renaming view fails, archived .frm for view is
missing after downgrade
TABLE_LIST: the revision field has been removed.
``FLUSH TABLES WITH READ LOCK''
Concurrent execution of 1) multitable update with a
NATURAL/USING join and 2) a such query as "FLUSH TABLES
WITH READ LOCK" or "ALTER TABLE" of updating table led
to a server crash.
The mysql_multi_update_prepare() function call is optimized
to lock updating tables only, so it postpones locking to
the last, and if locking fails, it does cleanup of modified
syntax structures and repeats a query analysis. However,
that cleanup procedure was incomplete for NATURAL/USING join
syntax data: 1) some Field_item items pointed into freed
table structures, and 2) the TABLE_LIST::join_columns fields
was not reset.
Major change:
short-living Field *Natural_join_column::table_field has
been replaced with long-living Item*.
mysql-test/r/lock_multi.result:
Added test case for bug #38691.
mysql-test/t/lock_multi.test:
Added test case for bug #38691.
sql/item.cc:
Bug #38691: segfault/abort in ``UPDATE ...JOIN'' while
``FLUSH TABLES WITH READ LOCK''
The Item_field constructor has been modified to allocate
and copy original database/table/field names always (not
during PS preparation/1st execution only), because
an initialization of Item_field items with a pointer to
short-living Field structures is a common practice.
sql/sql_base.cc:
Bug #38691: segfault/abort in ``UPDATE ...JOIN'' while
``FLUSH TABLES WITH READ LOCK''
1) Type adjustment for Natural_join_column::table_field
(Field to Item_field);
2) The setup_natural_join_row_types function has been
updated to take into account new
first_natural_join_processing flag to skip unnecessary
reinitialization of Natural_join_column::join_columns
during table reopening after lock_tables() failure
(like the 'first_execution' flag for PS).
sql/sql_lex.cc:
Bug #38691: segfault/abort in ``UPDATE ...JOIN'' while
``FLUSH TABLES WITH READ LOCK''
Initialization of the new
st_select_lex::first_natural_join_processing flag has
been added.
sql/sql_lex.h:
Bug #38691: segfault/abort in ``UPDATE ...JOIN'' while
``FLUSH TABLES WITH READ LOCK''
The st_select_lex::first_natural_join_processing flag
has been added to skip unnecessary rebuilding of
NATURAL/USING JOIN structures during table reopening
after lock_tables failure.
sql/sql_update.cc:
Bug #38691: segfault/abort in ``UPDATE ...JOIN'' while
``FLUSH TABLES WITH READ LOCK''
Extra cleanup calls have been added to reset
Natural_join_column::table_field items.
sql/table.cc:
Bug #38691: segfault/abort in ``UPDATE ...JOIN'' while
``FLUSH TABLES WITH READ LOCK''
Type adjustment for Natural_join_column::table_field
(Field to Item_field).
sql/table.h:
Bug #38691: segfault/abort in ``UPDATE ...JOIN'' while
``FLUSH TABLES WITH READ LOCK''
Type of the Natural_join_column::table_field field has
been changed from Field that points into short-living
TABLE memory to long-living Item_field that can be
linked to (fixed) reopened table.
Problem was a mutex added in bug n 27405 for solving a problem
with auto_increment in partitioned innodb tables.
(in ha_partition::write_row over partitions file->ha_write_row)
Solution is to use the patch for bug#33479, which refines the
usage of mutexes for auto_increment.
Backport of bug-33479 from 6.0:
Bug-33479: auto_increment failures in partitioning
Several problems with auto_increment in partitioning
(with MyISAM, InnoDB. Locking issues, not handling
multi-row INSERTs properly etc.)
Changed the auto_increment handling for partitioning:
Added a ha_data variable in table_share for storage engine specific data
such as auto_increment value handling in partitioning, also see WL 4305
and using the ha_data->mutex to lock around read + update.
The idea is this:
Store the table's reserved auto_increment value in
the TABLE_SHARE and use a mutex to, lock it for reading and updating it
and unlocking it, in one block. Only accessing all partitions
when it is not initialized.
Also allow reservations of ranges, and if no one has done a reservation
afterwards, lower the reservation to what was actually used after
the statement is done (via release_auto_increment from WL 3146).
The lock is kept from the first reservation if it is statement based
replication and a multi-row INSERT statement where the number of
candidate rows to insert is not known in advance (like INSERT SELECT,
LOAD DATA, unlike INSERT VALUES (row1), (row2),,(rowN)).
This should also lead to better concurrancy (no need to have a mutex
protection around write_row in all cases)
and work with any local storage engine.
mysql-test/suite/parts/inc/partition_auto_increment.inc:
Bug#38804: Query deadlock causes all tables to be inaccessible.
Backporting from 6.0 of:
Bug-33479: auto_increment failures in partitioning
Test source file for testing auto_increment
mysql-test/suite/parts/r/partition_auto_increment_archive.result:
Bug#38804: Query deadlock causes all tables to be inaccessible.
Backporting from 6.0 of:
Bug-33479: auto_increment failures in partitioning
result file for testing auto_increment
mysql-test/suite/parts/r/partition_auto_increment_blackhole.result:
Bug#38804: Query deadlock causes all tables to be inaccessible.
Backporting from 6.0 of:
Bug-33479: auto_increment failures in partitioning
result file for testing auto_increment
mysql-test/suite/parts/r/partition_auto_increment_innodb.result:
Bug#38804: Query deadlock causes all tables to be inaccessible.
Backporting from 6.0 of:
Bug-33479: auto_increment failures in partitioning
result file for testing auto_increment
mysql-test/suite/parts/r/partition_auto_increment_memory.result:
Bug#38804: Query deadlock causes all tables to be inaccessible.
Backporting from 6.0 of:
Bug-33479: auto_increment failures in partitioning
result file for testing auto_increment
mysql-test/suite/parts/r/partition_auto_increment_myisam.result:
Bug#38804: Query deadlock causes all tables to be inaccessible.
Backporting from 6.0 of:
Bug-33479: auto_increment failures in partitioning
result file for testing auto_increment
mysql-test/suite/parts/r/partition_auto_increment_ndb.result:
Bug#38804: Query deadlock causes all tables to be inaccessible.
Backporting from 6.0 of:
Bug-33479: auto_increment failures in partitioning
result file for testing auto_increment
mysql-test/suite/parts/t/partition_auto_increment_archive.test:
Bug#38804: Query deadlock causes all tables to be inaccessible.
Backporting from 6.0 of:
Bug-33479: auto_increment failures in partitioning
test file for testing auto_increment
mysql-test/suite/parts/t/partition_auto_increment_blackhole.test:
Bug#38804: Query deadlock causes all tables to be inaccessible.
Backporting from 6.0 of:
Bug-33479: auto_increment failures in partitioning
test file for testing auto_increment
mysql-test/suite/parts/t/partition_auto_increment_innodb.test:
Bug#38804: Query deadlock causes all tables to be inaccessible.
Backporting from 6.0 of:
Bug-33479: auto_increment failures in partitioning
test file for testing auto_increment
mysql-test/suite/parts/t/partition_auto_increment_memory.test:
Bug#38804: Query deadlock causes all tables to be inaccessible.
Backporting from 6.0 of:
Bug-33479: auto_increment failures in partitioning
test file for testing auto_increment
mysql-test/suite/parts/t/partition_auto_increment_myisam.test:
Bug#38804: Query deadlock causes all tables to be inaccessible.
Backporting from 6.0 of:
Bug-33479: auto_increment failures in partitioning
test file for testing auto_increment
mysql-test/suite/parts/t/partition_auto_increment_ndb.test:
Bug#38804: Query deadlock causes all tables to be inaccessible.
Backporting from 6.0 of:
Bug-33479: auto_increment failures in partitioning
test file for testing auto_increment
sql/ha_partition.cc:
Bug#38804: Query deadlock causes all tables to be inaccessible.
Backporting from 6.0 of:
Bug-33479: Failures using auto_increment and partitioning
Changed ha_partition::get_auto_increment from file->get_auto_increment
to file->info(HA_AUTO_STATUS), since it is works better with InnoDB
(InnoDB can have issues with partitioning and auto_increment,
where get_auto_increment sometimes can return a non updated value.)
Using the new table_share->ha_data for keeping the auto_increment
value, shared by all instances of the same table.
It is read+updated when holding a auto_increment specific mutex.
Also added release_auto_increment to decrease gaps if possible.
And a lock for multi-row INSERT statements where the number of candidate
rows to insert is not known in advance (like INSERT SELECT, LOAD DATA;
Unlike INSERT INTO (row1),(row2),,(rowN)).
Fixed a small bug, copied++ to (*copied)++ and the same for deleted.
Changed from current_thd, to ha_thd()
sql/ha_partition.h:
Bug#38804: Query deadlock causes all tables to be inaccessible.
Backporting from 6.0 of:
Bug-33479: Failures using auto_increment and partitioning
Added a new struct HA_DATA_PARTITION to be used in table_share->ha_data
Added a private function to set auto_increment values if needed
Removed the restore_auto_increment (the hander version is better)
Added lock/unlock functions for auto_increment handling.
Changed copied/deleted to const.
sql/handler.h:
Bug#38804: Query deadlock causes all tables to be inaccessible.
Backporting from 6.0 of:
Bug-33479: auto_increment failures in partitioning
Added const for changed_partitions
Added comments about SQLCOM_TRUNCATE for delete_all_rows
sql/table.h:
Bug#38804: Query deadlock causes all tables to be inaccessible.
Backporting from 6.0 of:
Bug-33479: Failures using auto_increment and partitioning
Added a variable in table_share: ha_data for storage of storage engine
specific data (such as auto_increment handling in partitioning).
This patch also fixes bugs 36963 and 35600.
- In many places a view was confused with an anonymous derived
table, i.e. access checking was skipped. Fixed by introducing a
predicate to tell the difference between named and anonymous
derived tables.
- When inserting fields for "SELECT * ", there was no
distinction between base tables and views, where one should be
made. View privileges are checked elsewhere.
mysql-test/include/grant_cache.inc:
Bug#36086: Changed test case.
mysql-test/r/grant2.result:
Bug#36086: Changed test result.
mysql-test/r/grant_cache_no_prot.result:
Bug#36086: Changed test result.
mysql-test/r/grant_cache_ps_prot.result:
Bug#36086: Changed test result.
mysql-test/r/view_grant.result:
Bug#36086: Test result.
mysql-test/t/grant2.test:
Bug#36086: Changed test case.
mysql-test/t/view_grant.test:
Bug#36086: Test case.
sql/item.cc:
Bug#36086: Replaced conditional with new methods.
sql/sql_acl.cc:
Bug no 35600:
In mysql_table_grant:
Replaced conditional with the new accessor method.
In check_grant:
- Changed the requirement table->derived != null to
checking all anonymous derived tables.
- Use of the accessor methods for getting object and database
names.
Bug#36086: In check_grant_all_columns:
- Updated comment. This function is now called for views
as well.
- The error message should not disclose any column names
unless the user has privilege to see all column names.
- Changed names of Field_iterator_table_ref methods.
sql/sql_base.cc:
Bug no 36963: In insert_fields()
- Commented.
- We should call check_grant_all_columns() for views in
this case.
- Changed names of Field_iterator_table_ref methods.
- We should not disclose column names in the error message
when the user has no approprate privilege.
sql/sql_cache.cc:
Bug#36086: Replaced test with new predicate method.
sql/sql_derived.cc:
Bug#36086: commenting only. Updated and doxygenated
comment for mysql_derived_prepare().
sql/sql_parse.cc:
Bug no 35600:
- In check_single_table_access:
Due to the bug, check_grant would raise an error for a
SHOW CREATE TABLE command for a TEMPTABLE view. It should in
fact not be be invoked in this case. This table privilege
is checked already.
There is a test case for this in information_schema_db.test.
- In check_access: replaced table->derived
sql/table.cc:
Bug#36086:
- In TABLE_LIST::set_underlying_merge():
Commenting only. Doxygenated, corrected spelling,
added.
- Renamed table_name() and db_name() methods of
Field_iterator_table_ref in order to be consistent
with new methods in TABLE_LIST.
sql/table.h:
Bug#36086:
- Commented GRANT_INFO.
- Added a predicate is_anonymous_derived_table() to
TABLE_LIST.
- Added get_table_name() and get_db_name() to
TABLE_LIST in order to hide the disparate
representation of these properties.
Tables in the table definition cache are keeping a cache buffer for blob
fields which can consume a lot of memory.
This patch introduces a maximum size threshold for these buffers.
sql/sql_base.cc:
Added function free_field_buffers_larger_than to reclaim memory from blob
field buffers too large to be cached.
sql/table.cc:
Added function free_field_buffers_larger_than
PREPARE": rename members, methods, classes to follow the spec
(a code review request)
sql/mysql_priv.h:
enum_metadata_type -> enum_table_ref_type
sql/sp_head.cc:
Metadata_version_observer -> Reprepare_observer
sql/sql_base.cc:
metadata -> table_ref
sql/sql_class.cc:
Replace an abstract interface with a concrete implementation.
sql/sql_class.h:
enum_metadata_type -> enum_table_ref_type
sql/sql_prepare.cc:
Move implementation of Execute_observer to sql_class.cc and
rename the class to Reprepare_observer.
Use getters instead of direct access to the members.
sql/table.h:
metadata -> table_ref
"Crash in subquery code when in PS and table DDL changed after PREPARE"
include/my_sys.h:
Add two new flags for my_error(). These flags help parameterize
behavoiur of my_message_sql()
sql/item.cc:
Update comments.
Fix a typo in Item_param::set_param_type_and_swap_value()
sql/mysqld.cc:
Implement two additional flags for my_error():
- if ME_NO_SP_HANDLER is specified, ignore stored procedure continue/
exit handlers
- if ME_NO_WARNING_FOR_ERROR is specified, do not push warning
sql/sql_base.cc:
Update comments.
Rename a few methods.
sql/sql_class.h:
Update and improve comments.
sql/sql_prepare.cc:
Update comments.
Style changes.
sql/table.h:
Update comments.
Style changes.
Rename a few methods.
tests/mysql_client_test.c:
Zero the bind array, to follow C API requirements.
into bodhi.(none):/opt/local/work/mysql-5.1-27430
include/my_global.h:
Auto merged
mysql-test/r/grant.result:
Auto merged
mysql-test/t/disabled.def:
Auto merged
mysql-test/t/grant.test:
Auto merged
sql/item.cc:
Auto merged
sql/mysql_priv.h:
Auto merged
sql/mysqld.cc:
Auto merged
sql/set_var.cc:
Auto merged
sql/sql_acl.cc:
Auto merged
sql/sql_class.cc:
Auto merged
sql/sql_class.h:
Auto merged
sql/sql_parse.cc:
Auto merged
sql/sql_table.cc:
Auto merged
sql/sql_yacc.yy:
Auto merged
sql/table.h:
Auto merged
storage/myisam/mi_create.c:
Auto merged
tests/mysql_client_test.c:
Auto merged
sql/share/errmsg.txt:
Manual merge.
Add metadata validation to ~20 more SQL commands. Make sure that
these commands actually work in ps-protocol, since until now they
were enabled, but not carefully tested.
Fixes the ml003 bug found by Matthias during internal testing of the
patch.
mysql-test/r/ps_ddl.result:
Update test results (WL#4165)
mysql-test/t/ps_ddl.test:
Cover with tests metadata validation of 26 SQL statements.
sql/mysql_priv.h:
Fix the name in the comment.
sql/sp_head.cc:
Changed the way the observer is removed in case of stored procedures
to support validation prepare stmt from "call p1(<expr>)": whereas
tables used in the expression must be validated, substatements
of p1 must not.
The previous scheme used to silence the observer only in stored
functions and triggers.
sql/sql_class.cc:
Now the observer is silenced in sp_head::execute(). Remove it from
Sub_statement_state.
sql/sql_class.h:
Now the observer is silenced in sp_head::execute(). Remove it from
Sub_statement_state.
sql/sql_parse.cc:
Add CF_REEXECUTION_FRAGILE to 20 more SQLCOMs that need it.
sql/sql_prepare.cc:
Add metadata validation to ~20 new SQLCOMs that need it.
Fix memory leaks with expressions used in SHOW DATABASES and CALL
(and prepared statements).
We need to fix all expressions at prepare, since if these expressions
use subqueries, there are one-time transformations of the parse
tree that must be done at prepare.
List of fixed commands includes: SHOW TABLES, SHOW DATABASES,
SHOW TRIGGERS, SHOW EVENTS, SHOW OPEN TABLES,SHOW KEYS, SHOW FIELDS,
SHOW COLLATIONS, SHOW CHARSETS, SHOW VARIABLES, SHOW TATUS, SHOW TABLE
STATUS, SHOW PROCEDURE STATUS, SHOW FUNCTION STATUS, CALL.
Add comment to set_parameters().
sql/table.h:
Update comments.
WL#4165 Prepared statements: validation
WL#4166 Prepared statements: automatic re-prepare
Fixes
Bug#27430 Crash in subquery code when in PS and table DDL changed after PREPARE
Bug#27690 Re-execution of prepared statement after table was replaced with a view crashes
Bug#27420 A combination of PS and view operations cause error + assertion on shutdown
The basic idea of the patch is to keep track of table metadata between
prepared statement prepare and execute. If some table used in the statement
has changed, the prepared statement is re-prepared before execution.
See WL#4165 and WL#4166 contents and comments in the code for details
of the implementation.
include/my_global.h:
Remove 'register' keyword to avoid warnings when swapping large structures
that don't fit into a register. Any modern compiler is capable of placing
a variable in a register when that would benefit performance.
mysql-test/r/ps_1general.result:
Update test results: since now we re-prepare automatically,
more correct results are produced in prepare-ddl-execute scenario.
mysql-test/r/query_cache_merge.result:
Ensure that the table definition cache is large enough for
the test to pass in --ps-protocol
mysql-test/r/trigger.result:
Update test results to reflect automatic statement reprepare.
mysql-test/t/disabled.def:
Enable ps_ddl.test, which now passes.
mysql-test/t/ps_1general.test:
Since now we re-execute prepared statements after DDL successfully,
change the test to produce repeatable results. Remove expectancy of
an error in one place where now we automatically reprepare the prepared
statement.
mysql-test/t/query_cache_merge.test:
Ensure the table definition cache is large enough for the test to pass
in --ps-protocol
mysql-test/t/trigger.test:
Sinc
sql/item.cc:
Implement Item_param "copy" functionality, used at re-prepare of
a prepared statement.
We copy the type of the original parameter, and move the assigned value,
if any. Sic, the value is "moved", since it can be quite big --
e.g. in case we deal with a LONG DATA parameter.
It's essential to move the value from the old parameter since
at the time of re-prepare the client packet with the necessary information
may be not available.
sql/item.h:
Declare a new method used for reprepare.
sql/my_decimal.h:
Implement "swap()" functionality of class my_decimal to be
able to easily swap two decimal values.
sql/mysql_priv.h:
Declare enum_metadata_type.
sql/mysqld.cc:
Implement a status variable for the number of reprepared statements.
sql/sql_base.cc:
Implement metadata version validation.
sql/share/errmsg.txt:
Add two new error messages: ER_NEED_REPREPARE and ER_PS_REBIND.
The first error (theoretically) never reaches the user.
It is issued by the metadata validation framework when a metadata version
has changed between prepare and execute. Later on it's intercepted
and the statement is automatically re-prepared. Only if the error
has occurred repeatedly MAX_REPREPARE_ATTEMTS (3) times do we
return it to the user.
The second error is issued when after re-prepare we discover
that the metadata we sent over to the client using the binary
protocol differs drammatically from the new result set metadata
that the reprepared statement produces (e.g. number of result
set columns is different).
sql/sql_class.cc:
Implement metadata version validation framework.
sql/sql_class.h:
Declarations for metadata version validation framework.
sql/sql_parse.cc:
Mark commands for which we must invalidate and reprepare a prepared
statement when metadata has changed.
sql/sql_prepare.cc:
Implement WL#4165 and WL#4166 (limited support of metadata validation
and re-prepare).
sql/table.h:
Implement metadata validation.
tests/mysql_client_test.c:
Add a test case for WL#4166
