2352 commits

Author	SHA1	Message	Date
Dmitry Lenev	6bf6272fda	Patch that refactors global read lock implementation and fixes ... bug #57006 "Deadlock between HANDLER and FLUSH TABLES WITH READ LOCK" and bug #54673 "It takes too long to get readlock for 'FLUSH TABLES WITH READ LOCK'". The first bug manifested itself as a deadlock which occurred when a connection, which had some table open through HANDLER statement, tried to update some data through DML statement while another connection tried to execute FLUSH TABLES WITH READ LOCK concurrently. What happened was that FTWRL in the second connection managed to perform first step of GRL acquisition and thus blocked all upcoming DML. After that it started to wait for table open through HANDLER statement to be flushed. When the first connection tried to execute DML it has started to wait for GRL/the second connection creating deadlock. The second bug manifested itself as starvation of FLUSH TABLES WITH READ LOCK statements in cases when there was a constant stream of concurrent DML statements (in two or more connections). This has happened because requests for protection against GRL which were acquired by DML statements were ignoring presence of pending GRL and thus the latter was starved. This patch solves both these problems by re-implementing GRL using metadata locks. Similar to the old implementation acquisition of GRL in new implementation is two-step. During the first step we block all concurrent DML and DDL statements by acquiring global S metadata lock (each DML and DDL statement acquires global IX lock for its duration). During the second step we block commits by acquiring global S lock in COMMIT namespace (commit code acquires global IX lock in this namespace). Note that unlike in old implementation acquisition of protection against GRL in DML and DDL is semi-automatic. We assume that any statement which should be blocked by GRL will either open and acquires write-lock on tables or acquires metadata locks on objects it is going to modify. For any such statement global IX metadata lock is automatically acquired for its duration. The first problem is solved because waits for GRL become visible to deadlock detector in metadata locking subsystem and thus deadlocks like one in the first bug become impossible. The second problem is solved because global S locks which are used for GRL implementation are given preference over IX locks which are acquired by concurrent DML (and we can switch to fair scheduling in future if needed). Important change: FTWRL/GRL no longer blocks DML and DDL on temporary tables. Before this patch behavior was not consistent in this respect: in some cases DML/DDL statements on temporary tables were blocked while in others they were not. Since the main use cases for FTWRL are various forms of backups and temporary tables are not preserved during backups we have opted for consistently allowing DML/DDL on temporary tables during FTWRL/GRL. Important change: This patch changes thread state names which are used when DML/DDL of FTWRL is waiting for global read lock. It is now either "Waiting for global read lock" or "Waiting for commit lock" depending on the stage on which FTWRL is. Incompatible change: To solve deadlock in events code which was exposed by this patch we have to replace LOCK_event_metadata mutex with metadata locks on events. As result we have to prohibit DDL on events under LOCK TABLES. This patch also adds extensive test coverage for interaction of DML/DDL and FTWRL. Performance of new and old global read lock implementations in sysbench tests were compared. There were no significant difference between new and old implementations. mysql-test/include/check_ftwrl_compatible.inc: Added helper script which allows to check that a statement is compatible with FLUSH TABLES WITH READ LOCK. mysql-test/include/check_ftwrl_incompatible.inc: Added helper script which allows to check that a statement is incompatible with FLUSH TABLES WITH READ LOCK. mysql-test/include/handler.inc: Adjusted test case to the fact that now DROP TABLE closes open HANDLERs for the table to be dropped before checking if there active FTWRL in this connection. mysql-test/include/wait_show_condition.inc: Fixed small error in the timeout message. The correct name of variable used as parameter for this script is "$condition" and not "$wait_condition". mysql-test/r/delayed.result: Added test coverage for scenario which triggered assert in metadata locking subsystem. mysql-test/r/events_2.result: Updated test results after prohibiting event DDL operations under LOCK TABLES. mysql-test/r/flush.result: Added test coverage for bug #57006 "Deadlock between HANDLER and FLUSH TABLES WITH READ LOCK". mysql-test/r/flush_read_lock.result: Added test coverage for various aspects of FLUSH TABLES WITH READ LOCK functionality. mysql-test/r/flush_read_lock_kill.result: Adjusted test case after replacing custom global read lock implementation with one based on metadata locks. Use new debug_sync point. Do not disable concurrent inserts as now InnoDB we always use InnoDB table. mysql-test/r/handler_innodb.result: Adjusted test case to the fact that now DROP TABLE closes open HANDLERs for the table to be dropped before checking if there active FTWRL in this connection. mysql-test/r/handler_myisam.result: Adjusted test case to the fact that now DROP TABLE closes open HANDLERs for the table to be dropped before checking if there active FTWRL in this connection. mysql-test/r/mdl_sync.result: Adjusted test case after replacing custom global read lock implementation with one based on metadata locks. Replaced usage of GRL-specific debug_sync's with appropriate sync points in MDL subsystem. mysql-test/suite/perfschema/r/dml_setup_instruments.result: Updated test results after removing global COND_global_read_lock condition variable. mysql-test/suite/perfschema/r/func_file_io.result: Ensure that this test doesn't affect subsequent tests. At the end of its execution enable back P_S instrumentation which this test disables at some point. mysql-test/suite/perfschema/r/func_mutex.result: Ensure that this test doesn't affect subsequent tests. At the end of its execution enable back P_S instrumentation which this test disables at some point. mysql-test/suite/perfschema/r/global_read_lock.result: Adjusted test case to take into account that new GRL implementation is based on MDL. mysql-test/suite/perfschema/r/server_init.result: Adjusted test case after replacing custom global read lock implementation with one based on MDL and replacing LOCK_event_metadata mutex with metadata lock. mysql-test/suite/perfschema/t/func_file_io.test: Ensure that this test doesn't affect subsequent tests. At the end of its execution enable back P_S instrumentation which this test disables at some point. mysql-test/suite/perfschema/t/func_mutex.test: Ensure that this test doesn't affect subsequent tests. At the end of its execution enable back P_S instrumentation which this test disables at some point. mysql-test/suite/perfschema/t/global_read_lock.test: Adjusted test case to take into account that new GRL implementation is based on MDL. mysql-test/suite/perfschema/t/server_init.test: Adjusted test case after replacing custom global read lock implementation with one based on MDL and replacing LOCK_event_metadata mutex with metadata lock. mysql-test/suite/rpl/r/rpl_tmp_table_and_DDL.result: Updated test results after prohibiting event DDL under LOCK TABLES. mysql-test/t/delayed.test: Added test coverage for scenario which triggered assert in metadata locking subsystem. mysql-test/t/events_2.test: Updated test case after prohibiting event DDL operations under LOCK TABLES. mysql-test/t/flush.test: Added test coverage for bug #57006 "Deadlock between HANDLER and FLUSH TABLES WITH READ LOCK". mysql-test/t/flush_block_commit.test: Adjusted test case after changing thread state name which is used when COMMIT waits for FLUSH TABLES WITH READ LOCK from "Waiting for release of readlock" to "Waiting for commit lock". mysql-test/t/flush_block_commit_notembedded.test: Adjusted test case after changing thread state name which is used when DML waits for FLUSH TABLES WITH READ LOCK. Now we use "Waiting for global read lock" in this case. mysql-test/t/flush_read_lock.test: Added test coverage for various aspects of FLUSH TABLES WITH READ LOCK functionality. mysql-test/t/flush_read_lock_kill-master.opt: We no longer need to use make_global_read_lock_block_commit_loop debug tag in this test. Instead we rely on an appropriate debug_sync point in MDL code. mysql-test/t/flush_read_lock_kill.test: Adjusted test case after replacing custom global read lock implementation with one based on metadata locks. Use new debug_sync point. Do not disable concurrent inserts as now InnoDB we always use InnoDB table. mysql-test/t/lock_multi.test: Adjusted test case after changing thread state names which are used when DML or DDL waits for FLUSH TABLES WITH READ LOCK to "Waiting for global read lock". mysql-test/t/mdl_sync.test: Adjusted test case after replacing custom global read lock implementation with one based on metadata locks. Replaced usage of GRL-specific debug_sync's with appropriate sync points in MDL subsystem. Updated thread state names which are used when DDL waits for FTWRL. mysql-test/t/trigger_notembedded.test: Adjusted test case after changing thread state names which are used when DML or DDL waits for FLUSH TABLES WITH READ LOCK to "Waiting for global read lock". sql/event_data_objects.cc: Removed Event_queue_element::status/last_executed_changed members and Event_queue_element::update_timing_fields() method. We no longer use this class for updating mysql.events once event is chosen for execution. Accesses to instances of this class in scheduler thread require protection by Event_queue::LOCK_event_queue mutex and we try to avoid updating table while holding this lock. sql/event_data_objects.h: Removed Event_queue_element::status/last_executed_changed members and Event_queue_element::update_timing_fields() method. We no longer use this class for updating mysql.events once event is chosen for execution. Accesses to instances of this class in scheduler thread require protection by Event_queue::LOCK_event_queue mutex and we try to avoid updating table while holding this lock. sql/event_db_repository.cc: - Changed Event_db_repository methods to not release all metadata locks once they are done updating mysql.events table. This allows to keep metadata lock protecting against GRL and lock protecting particular event around until corresponding DDL statement is written to the binary log. - Removed logic for conditional update of "status" and "last_executed" fields from update_timing_fields_for_event() method. In the only case when this method is called now "last_executed" is always modified and tracking change of "status" is too much hassle. sql/event_db_repository.h: Removed logic for conditional update of "status" and "last_executed" fields from Event_db_repository:: update_timing_fields_for_event() method. In the only case when this method is called now "last_executed" is always modified and tracking change of "status" field is too much hassle. sql/event_queue.cc: Changed event scheduler code not to update mysql.events table while holding Event_queue::LOCK_event_queue mutex. Doing so led to a deadlock with a new GRL implementation. This deadlock didn't occur with old implementation due to fact that code acquiring protection against GRL ignored pending GRL requests (which lead to GRL starvation). One of goals of new implementation is to disallow GRL starvation and so we have to solve problem with this deadlock in a different way. sql/events.cc: Changed methods of Events class to acquire protection against GRL while perfoming DDL statement and keep it until statement is written to the binary log. Unfortunately this step together with new GRL implementation exposed deadlock involving Events::LOCK_event_metadata and GRL. To solve it Events::LOCK_event_metadata mutex was replaced with a metadata lock on event. As a side-effect events DDL has to be prohibited under LOCK TABLES even in cases when mysql.events table was explicitly locked for write. sql/events.h: Replaced Events::LOCK_event_metadata mutex with a metadata lock on event. sql/ha_ndbcluster.cc: Updated code after replacing custom global read lock implementation with one based on MDL. Since MDL subsystem should now be able to detect deadlocks involving metadata locks and GRL there is no need for special handling of active GRL. sql/handler.cc: Replaced custom implementation of global read lock with one based on metadata locks. Consequently when doing commit instead of calling method of Global_read_lock class to acquire protection against GRL we simply acquire IX in COMMIT namespace. sql/lock.cc: Replaced custom implementation of global read lock with one based on metadata locks. This step allows to expose wait for GRL to deadlock detector of MDL subsystem and thus succesfully resolve deadlocks similar to one behind bug #57006 "Deadlock between HANDLER and FLUSH TABLES WITH READ LOCK". It also solves problem with GRL starvation described in bug #54673 "It takes too long to get readlock for 'FLUSH TABLES WITH READ LOCK'" since metadata locks used by GRL give preference to FTWRL statement instead of DML statements (if needed in future this can be changed to fair scheduling). Similar to old implementation of acquisition of GRL is two-step. During the first step we block all concurrent DML and DDL statements by acquiring global S metadata lock (each DML and DDL statement acquires global IX lock for its duration). During the second step we block commits by acquiring global S lock in COMMIT namespace (commit code acquires global IX lock in this namespace). Note that unlike in old implementation acquisition of protection against GRL in DML and DDL is semi-automatic. We assume that any statement which should be blocked by GRL will either open and acquires write-lock on tables or acquires metadata locks on objects it is going to modify. For any such statement global IX metadata lock is automatically acquired for its duration. To support this change: - Global_read_lock::lock/unlock_global_read_lock and make_global_read_lock_block_commit methods were changed accordingly. - Global_read_lock::wait_if_global_read_lock() and start_waiting_global_read_lock() methods were dropped. It is now responsibility of code acquiring metadata locks opening tables to acquire protection against GRL by explicitly taking global IX lock with statement duration. - Global variables, mutex and condition variable used by old implementation was removed. - lock_routine_name() was changed to use statement duration for its global IX lock. It was also renamed to lock_object_name() as it now also used to take metadata locks on events. - Global_read_lock::set_explicit_lock_duration() was added which allows not to release locks used for GRL when leaving prelocked mode. sql/lock.h: - Renamed lock_routine_name() to lock_object_name() and changed its signature to allow its usage for events. - Removed broadcast_refresh() function. It is no longer needed with new GRL implementation. sql/log_event.cc: Release metadata locks with statement duration at the end of processing legacy event for LOAD DATA. This ensures that replication thread processing such event properly releases its protection against global read lock. sql/mdl.cc: Changed MDL subsystem to support new MDL-based implementation of global read lock. Added COMMIT and EVENTS namespaces for metadata locks. Changed thread state name for GLOBAL namespace to "Waiting for global read lock". Optimized MDL_map::find_or_insert() method to avoid taking m_mutex mutex when looking up MDL_lock objects for GLOBAL or COMMIT namespaces. We keep pre-created MDL_lock objects for these namespaces around and simply return pointers to these global objects when needed. Changed MDL_lock/MDL_scoped_lock to properly handle notification of insert delayed handler threads when FTWRL takes global S lock. Introduced concept of lock duration. In addition to locks with transaction duration which work in the way which is similar to how locks worked before (i.e. they are released at the end of transaction), locks with statement and explicit duration were introduced. Locks with statement duration are automatically released at the end of statement. Locks with explicit duration require explicit release and obsolete concept of transactional sentinel. * Changed MDL_request and MDL_ticket classes to support notion of duration. * Changed MDL_context to keep locks with different duration in different lists. Changed code handling ticket list to take this into account. * Changed methods responsible for releasing locks to take into account duration of tickets. Particularly public MDL_context::release_lock() method now only can release tickets with explicit duration (there is still internal method which allows to specify duration). To release locks with statement or transaction duration one have to use release_statement/transactional_locks() methods. * Concept of savepoint for MDL subsystem now has to take into account locks with statement duration. Consequently MDL_savepoint class was introduced and methods working with savepoints were updated accordingly. * Added methods which allow to set duration for one or all locks in the context. sql/mdl.h: Changed MDL subsystem to support new MDL-based implementation of global read lock. Added COMMIT and EVENTS namespaces for metadata locks. Introduced concept of lock duration. In addition to locks with transaction duration which work in the way which is similar to how locks worked before (i.e. they are released at the end of transaction), locks with statement and explicit duration were introduced. Locks with statement duration are automatically released at the end of statement. Locks with explicit duration require explicit release and obsolete concept of transactional sentinel. * Changed MDL_request and MDL_ticket classes to support notion of duration. * Changed MDL_context to keep locks with different duration in different lists. Changed code handling ticket list to take this into account. * Changed methods responsible for releasing locks to take into account duration of tickets. Particularly public MDL_context::release_lock() method now only can release tickets with explicit duration (there is still internal method which allows to specify duration). To release locks with statement or transaction duration one have to use release_statement/transactional_locks() methods. * Concept of savepoint for MDL subsystem now has to take into account locks with statement duration. Consequently MDL_savepoint class was introduced and methods working with savepoints were updated accordingly. * Added methods which allow to set duration for one or all locks in the context. sql/mysqld.cc: Removed global mutex and condition variables which were used by old implementation of GRL. Also we no longer need to initialize Events::LOCK_event_metadata mutex as it was replaced with metadata locks on events. sql/mysqld.h: Removed global variable, mutex and condition variables which were used by old implementation of GRL. sql/rpl_rli.cc: When slave thread closes tables which were open for handling of RBR events ensure that it releases global IX lock which was acquired as protection against GRL. sql/sp.cc: Adjusted code to the new signature of lock_object/routine_name(), to the fact that one now needs specify duration of lock when initializing MDL_request and to the fact that savepoints for MDL subsystem are now represented by MDL_savepoint class. sql/sp_head.cc: Ensure that statements in stored procedures release statement metadata locks and thus release their protectiong against GRL in proper moment in time. Adjusted code to the fact that one now needs specify duration of lock when initializing MDL_request. sql/sql_admin.cc: Adjusted code to the fact that one now needs specify duration of lock when initializing MDL_request. sql/sql_base.cc: - Implemented support for new approach to acquiring protection against global read lock. We no longer acquire such protection explicitly on the basis of statement flags. Instead we always rely on code which is responsible for acquiring metadata locks on object to be changed acquiring this protection. This is achieved by acquiring global IX metadata lock with statement duration. Code doing this also responsible for checking that current connection has no active GRL by calling an Global_read_lock::can_acquire_protection() method. Changed code in open_table() and lock_table_names() accordingly. Note that as result of this change DDL and DML on temporary tables is always compatible with GRL (before it was incompatible in some cases and compatible in other cases). - To speed-up code acquiring protection against GRL introduced m_has_protection_against_grl member in Open_table_context class. It indicates that protection was already acquired sometime during open_tables() execution and new attempts can be skipped. - Thanks to new GRL implementation calls to broadcast_refresh() became unnecessary and were removed. - Adjusted code to the fact that one now needs specify duration of lock when initializing MDL_request and to the fact that savepoints for MDL subsystem are now represented by MDL_savepoint class. sql/sql_base.h: Adjusted code to the fact that savepoints for MDL subsystem are now represented by MDL_savepoint class. Also introduced Open_table_context::m_has_protection_against_grl member which allows to avoid acquiring protection against GRL while opening tables if such protection was already acquired. sql/sql_class.cc: Changed THD::leave_locked_tables_mode() after transactional sentinel for metadata locks was obsoleted by introduction of locks with explicit duration. sql/sql_class.h: - Adjusted code to the fact that savepoints for MDL subsystem are now represented by MDL_savepoint class. - Changed Global_read_lock class according to changes in global read lock implementation: * wait_if_global_read_lock and start_waiting_global_read_lock are now gone. Instead code needing protection against GRL has to acquire global IX metadata lock with statement duration itself. To help it new can_acquire_protection() was introduced. Also as result of the above change m_protection_count member is gone too. * Added m_mdl_blocks_commits_lock member to store metadata lock blocking commits. * Adjusted code to the fact that concept of transactional sentinel was obsoleted by concept of lock duration. - Removed CF_PROTECT_AGAINST_GRL flag as it is no longer necessary. New GRL implementation acquires protection against global read lock automagically when statement acquires metadata locks on tables or other objects it is going to change. sql/sql_db.cc: Adjusted code to the fact that one now needs specify duration of lock when initializing MDL_request. sql/sql_handler.cc: Removed call to broadcast_refresh() function. It is no longer needed with new GRL implementation. Adjusted code after introducing duration concept for metadata locks. Particularly to the fact transactional sentinel was replaced with explicit duration. sql/sql_handler.h: Renamed mysql_ha_move_tickets_after_trans_sentinel() to mysql_ha_set_explicit_lock_duration() after transactional sentinel was obsoleted by locks with explicit duration. sql/sql_insert.cc: Adjusted code handling delaying inserts after switching to new GRL implementation. Now connection thread initiating delayed insert has to acquire global IX lock in addition to metadata lock on table being inserted into. This IX lock protects against GRL and similarly to SW lock on table being inserted into has to be passed to handler thread in order to avoid deadlocks. sql/sql_lex.cc: LEX::protect_against_global_read_lock member is no longer necessary since protection against GRL is automatically taken by code acquiring metadata locks/opening tables. sql/sql_lex.h: LEX::protect_against_global_read_lock member is no longer necessary since protection against GRL is automatically taken by code acquiring metadata locks/opening tables. sql/sql_parse.cc: - Implemented support for new approach to acquiring protection against global read lock. We no longer acquire such protection explicitly on the basis of statement flags. Instead we always rely on code which is responsible for acquiring metadata locks on object to be changed acquiring this protection. This is achieved by acquiring global IX metadata lock with statement duration. This lock is automatically released at the end of statement execution. - Changed implementation of CREATE/DROP PROCEDURE/FUNCTION not to release metadata locks and thus protection against of GRL in the middle of statement execution. - Adjusted code to the fact that one now needs specify duration of lock when initializing MDL_request and to the fact that savepoints for MDL subsystem are now represented by MDL_savepoint class. sql/sql_prepare.cc: Adjusted code to the to the fact that savepoints for MDL subsystem are now represented by MDL_savepoint class. sql/sql_rename.cc: With new GRL implementation there is no need to explicitly acquire protection against GRL before renaming tables. This happens automatically in code which acquires metadata locks on tables being renamed. sql/sql_show.cc: Adjusted code to the fact that one now needs specify duration of lock when initializing MDL_request and to the fact that savepoints for MDL subsystem are now represented by MDL_savepoint class. sql/sql_table.cc: - With new GRL implementation there is no need to explicitly acquire protection against GRL before dropping tables. This happens automatically in code which acquires metadata locks on tables being dropped. - Changed mysql_alter_table() not to release lock on new table name explicitly and to rely on automatic release of locks at the end of statement instead. This was necessary since now MDL_context::release_lock() is supported only for locks for explicit duration. sql/sql_trigger.cc: With new GRL implementation there is no need to explicitly acquire protection against GRL before changing table triggers. This happens automatically in code which acquires metadata locks on tables which triggers are to be changed. sql/sql_update.cc: Fix bug exposed by GRL testing. During prepare phase acquire only S metadata locks instead of SW locks to keep prepare of multi-UPDATE compatible with concurrent LOCK TABLES WRITE and global read lock. sql/sql_view.cc: With new GRL implementation there is no need to explicitly acquire protection against GRL before creating view. This happens automatically in code which acquires metadata lock on view to be created. sql/sql_yacc.yy: LEX::protect_against_global_read_lock member is no longer necessary since protection against GRL is automatically taken by code acquiring metadata locks/opening tables. sql/table.cc: Adjusted code to the fact that one now needs specify duration of lock when initializing MDL_request. sql/table.h: Adjusted code to the fact that one now needs specify duration of lock when initializing MDL_request. sql/transaction.cc: Replaced custom implementation of global read lock with one based on metadata locks. Consequently when doing commit instead of calling method of Global_read_lock class to acquire protection against GRL we simply acquire IX in COMMIT namespace. Also adjusted code to the fact that MDL savepoint is now represented by MDL_savepoint class.	2010-11-11 20:11:05 +03:00
Luis Soares	1602ffb8ab	BUG#57899: Certain reserved words should not be reserved ... In MySQL 5.5 the new reserved words include: SLOW as in FLUSH SLOW LOGS GENERAL as in FLUSH GENERAL LOGS IGNORE_SERVER_IDS as in CHANGE MASTER ... IGNORE_SERVER_IDS MASTER_HEARTBEAT_PERIOD as in CHANGE MASTER ... MASTER_HEARTBEAT_PERIOD These are not reserved words in standard SQL, or in Oracle 11g, and as such, may affect existing applications. We fix this by adding the new words to the list of keywords that are allowed for labels in SPs. mysql-test/t/keywords.test: Test case that checks that the target words can be used for naming fields in a table or as local routine variable names.	2010-11-03 14:51:52 +00:00
Dmitry Shulga	333434d23b	Auto-merge from mysql-5.1-bugteam for bug#36742.	2010-10-13 13:27:03 +07:00
Dmitry Shulga	8169faec27	Fixed bug#36742 - GRANT hostname case handling inconsistent. ... mysql-test/r/grant.result: It was added result for test case for bug#36742. mysql-test/t/grant.test: It was added test case for bug#36742. sql/sql_yacc.yy: It was added convertation of host name part of user name to lowercase.	2010-10-13 12:28:58 +07:00
Luis Soares	fcc741f33f	BUG#54144: manual merged bzr bundle from bug report.	2010-10-08 00:34:59 +01:00
Luis Soares	06e921818a	BUG#54144: ER_SLAVE_HEARTBEAT_VALUE_OUT_OF_RANGE is hard coded ... The error message for ER_SLAVE_HEARTBEAT_VALUE_OUT_OF_RANGE was hard coded. Additionally, the same error was used in three separate error symptoms: 1. when heartbeat period exceeds the value of slave_net_timeout, 2. when it is smaller than 1 milisecond and 3. when it was not in range, ie, either negative or greater than the maximum allowed. We fix this by splitting into three distinct errors and by removing the message from the source code and moving it to the errmsg-utf8.txt file.	2010-10-07 16:38:23 +01:00
Davi Arnaut	a5efb91dea	Bug#49938: Failing assertion: inode or deadlock in fsp/fsp0fsp.c ... 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.	2010-10-06 11:34:28 -03:00
Georgi Kodinov	8789c79723	merge	2010-10-04 15:42:16 +03:00
Mattias Jonsson	fbb49d80eb	merge	2010-10-01 15:32:03 +02:00
Jon Olav Hauglid	68f87c72c0	Bug #56678 Valgrind warnings from binlog.binlog_unsafe ... After the patch for Bug#54579, multi inserts done with INSERT DELAYED are binlogged as normal INSERT. During processing of the statement, a new query string without the DELAYED keyword is made. The problem was that this new string was incorrectly made when the INSERT DELAYED was part of a prepared statement - data was read outside the allocated buffer. The reason for this bug was that a pointer to the position of the DELAYED keyword inside the query string was stored when parsing the statement. This pointer was then later (at runtime) used (via pointer subtraction) to find the number of characters to skip when making a new query string without DELAYED. But when the statement was re-executed as part of a prepared statement, the original pointer would be invalid and the pointer subtraction would give a wrong/random result. This patch fixes the problem by instead storing the offsets from the beginning of the query string to the start and end of the DELAYED keyword. These values will not depend on the memory position of the query string at runtime and therefore not give wrong results when the statement is executed in a prepared statement. This bug was a regression introduced by the patch for Bug#54579. No test case added as this bug is already covered by the existing binlog.binlog_unsafe test case when running with valgrind.	2010-09-24 10:44:09 +02:00
Jon Olav Hauglid	f89287cac4	Bug #54920 Stored functions are allowed in HANDLER statements, ... but broken. Before this patch, it was allowed to use stored functions in HANDLER ... READ statements. The problem was that this functionality was not really supported by the code. Proper locking would for example not be performed, and it was also possible to break replication by having stored functions that performed updates. This patch disallows the use of stored functions in HANDLER ... READ. Any such statement will now give an ER_NOT_SUPPORTED_YET error. This is an incompatible change and should be reflected in the documentation. Test case added to handler_myisam/handler_innodb.test.	2010-09-24 09:18:16 +02:00
Georgi Kodinov	353739fdef	merge of mysql-5.5 into mysql-5.5-wl1054	2010-09-20 17:17:32 +03:00
Dmitry Lenev	65a438d87a	Fix for bug #55273 "FLUSH TABLE tm WITH READ LOCK for Merge ... table causes assert failure". Attempting to use FLUSH TABLE table_list WITH READ LOCK statement for a MERGE table led to an assertion failure if one of its children was not present in the list of tables to be flushed. The problem was not visible in non-debug builds. The assertion failure was caused by the fact that in such situations FLUSH TABLES table_list WITH READ LOCK implementation tried to use (e.g. lock) such child tables without acquiring metadata lock on them. This happened because when opening tables we assumed metadata locks on all tables were already acquired earlier during statement execution and a such assumption was false for MERGE children. This patch fixes the problem by ensuring at open_tables() time that we try to acquire metadata locks on all tables to be opened. For normal tables such requests are satisfied instantly since locks are already acquired for them. For MERGE children metadata locks are acquired in normal fashion. Note that FLUSH TABLES merge_table WITH READ LOCK will lock for read both the MERGE table and its children but will flush only the MERGE table. To flush children one has to mention them in table list explicitly. This is expected behavior and it is consistent with usage patterns for this statement (e.g. in mysqlhotcopy script). mysql-test/r/flush.result: Added test case for bug #55273 "FLUSH TABLE tm WITH READ LOCK for Merge table causes assert failure". mysql-test/t/flush.test: Added test case for bug #55273 "FLUSH TABLE tm WITH READ LOCK for Merge table causes assert failure". sql/sql_base.cc: Changed lock_table_names() to support newly introduced MYSQL_OPEN_SKIP_SCOPED_MDL_LOCK flag. sql/sql_base.h: Introduced MYSQL_OPEN_SKIP_SCOPED_MDL_LOCK flag for open_tables() and lock_table_names() which allows to skip acquiring of global and schema-scope locks when SNW, SNRW or X metadata locks are acquired. sql/sql_reload.cc: Changed "FLUSH TABLES table_list WITH READ LOCK" code not to cause assert about missing metadata locks when MERGE table is flushed without one of its underlying tables. To achieve this we no longer call open_and_lock_tables() with MYSQL_OPEN_HAS_MDL_LOCK flag so this function automatically acquires metadata locks on MERGE children if such lock has not been already acquired at earlier stage. Instead we call this function with MYSQL_OPEN_SKIP_SCOPED_MDL_LOCK flag to suppress acquiring of global IX lock in order to keep FLUSH TABLES table_list WITH READ LOCK compatible with FLUSH TABLE WITH READ LOCK. Also changed implementation to use lock_table_names() function for pre-acquiring of metadata locks instead of custom code. To implement this change moved setting of open_type member for table list elements to parser. sql/sql_yacc.yy: Now we set acceptable type of table for FLUSH TABLES table_list WITH READ LOCK at parsing time instead of execution time.	2010-09-09 18:29:14 +04:00
Alexander Nozdrin	d88532110f	Auto-merge from mysql-5.5.	2010-09-01 17:12:42 +04:00
Gleb Shchepa	da9c598a88	automerge 5.1-bugteam --> 5.5-merge (bug 53034)	2010-08-31 02:22:01 +04:00
Gleb Shchepa	ccab4d8771	Bug #53034: Multiple-table DELETE statements not accepting ... "Access compatibility" syntax The "wild" "DELETE FROM table_name.* ... USING ..." syntax for multi-table DELETE statements is documented but it was lost in the fix for the bug 30234. The table_ident_opt_wild parser rule has been added to restore the lost syntax. mysql-test/r/delete.result: Test case for bug #53034. mysql-test/t/delete.test: Test case for bug #53034. sql/sql_yacc.yy: Bug #53034: Multiple-table DELETE statements not accepting "Access compatibility" syntax The table_ident_opt_wild parser rule has been added to restore the lost syntax. Note: simple extending of table_ident with opt_wild in the table_alias_ref rule is not acceptable, because a) it adds one conflict more and b) this conflict resolves in the inappropriate way.	2010-08-31 02:16:38 +04:00
Mattias Jonsson	86327002fe	Bug#50036: Inconsistent errors when using TIMESTAMP columns/expressions ... It was hard to understand what the error really meant. The error checking in partitioning is done in several different parts during the execution of a query which can make it hard to return useful errors. Added a new error for bad VALUES part in the per PARTITION clause. Using the more verbose error that a column is not allowed in the partitioning function instead of just that the function is not allowed. mysql-test/r/partition.result: changed error to be more specific mysql-test/r/partition_error.result: updated result mysql-test/std_data/parts/t1TIMESTAMP.frm: .frm file of CREATE TABLE t1 (a TIMESTAMP) PARTITION BY HASH(TO_DAYS(a)); mysql-test/t/partition.test: changed error to be more specific mysql-test/t/partition_error.test: Added test (also for verifying behaviour of previously created tables which is no longer allowed). Updated expected errors in other places sql/partition_info.cc: Added function report_part_expr_error to be able to return a more specific error. Renamed fix_func_partition to fix_partition_values since the function really fixes/checks the VALUES clause. sql/partition_info.h: removed part_result_type, since it was unused. renamed fix_funk_partition->fix_partition_values added report_part_expr_error sql/share/errmsg-utf8.txt: Added a more specific error. sql/sql_partition.cc: made use of report_part_expr_error to get a more specific error. sql/sql_yacc.yy: Changed error message to be more specific. And return an other error code.	2010-08-30 17:33:55 +02:00
unknown	89f3fec1e3	Bug #54579 Wrong unsafe warning for INSERT DELAYED in SBR ... The lock_type is upgrade to TL_WRITE from TL_WRITE_DELAYED for INSERT DELAYED when inserting multi values in one statement. It's safe. But it causes an unsafe warning in SBR. Make INSERT DELAYED safe by logging it as INSERT without DELAYED. mysql-test/extra/binlog_tests/binlog_insert_delayed.test: Updated the test file to test multi INSERT DELAYED statement is no longer causes an unsafe warning and binlogged as INSERT without DELAYED. mysql-test/extra/rpl_tests/create_recursive_construct.inc: Updated for the patch of bug#54579. mysql-test/suite/binlog/r/binlog_row_binlog.result: Updated for the patch of bug#54579. mysql-test/suite/binlog/r/binlog_statement_insert_delayed.result: Test result for BUG#54579. mysql-test/suite/binlog/r/binlog_stm_binlog.result: Updated for the patch of bug#54579. mysql-test/suite/binlog/r/binlog_unsafe.result: Updated for the patch of bug#54579. mysql-test/suite/binlog/t/binlog_unsafe.test: Updated for the patch of bug#54579. sql/sql_insert.cc: Added code to genetate a new query string for removing DELAYED keyword for multi INSERT DEALAYED statement. sql/sql_yacc.yy: Added code to record the DELAYED keyword position and remove the setting of unsafe statement for INSERT DELAYED statement	2010-08-30 14:03:28 +08:00
Jon Olav Hauglid	f2123f34e3	Merge from mysql-5.5-bugfixing to mysql-5.5-runtime	2010-08-18 13:55:37 +02:00
Jon Olav Hauglid	eb498cce4d	Manual merge from mysql-5.5-bugfixing to mysql-5.5-runtime.	2010-08-18 13:29:04 +02:00
unknown	d0d8bbed5e	WL#5370 Keep forward-compatibility when changing ... '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.	2010-08-18 17:35:41 +08:00
unknown	9d6811502e	WL#5370 Keep forward-compatibility when changing ... 'CREATE TABLE IF NOT EXISTS ... SELECT' behaviour BUG#55474, BUG#55499, BUG#55598, BUG#55616 and BUG#55777 are fixed in this patch too. This is the 5.1 part. It implements: - if the table exists, binlog two events: CREATE TABLE IF NOT EXISTS and INSERT ... SELECT - Insert nothing and binlog nothing on master if the existing object is a view. It only generates a warning that table already exists. mysql-test/r/trigger.result: Ather this patch, 'CREATE TABLE IF NOT EXISTS ... SELECT' will not insert anything if the creating table already exists and is a view. sql/sql_class.h: Declare virtual function write_to_binlog() for select_insert. It's used to binlog 'create select' sql/sql_insert.cc: Implement write_to_binlog(); Use write_to_binlog() instead of binlog_query() to binlog the statement. if the table exists, binlog two events: CREATE TABLE IF NOT EXISTS and INSERT ... SELECT sql/sql_lex.h: Declare create_select_start_with_brace and create_select_pos. They are helpful for binlogging 'create select' sql/sql_parse.cc: Do nothing on master if the existing object is a view. sql/sql_yacc.yy: Record the relative postion of 'SELECT' in the 'CREATE ...SELECT' statement. Record whether there is a '(' before the 'SELECT' clause.	2010-08-18 12:56:06 +08:00
Mattias Jonsson	b67924eb4e	Rename of sql_alter_table -> sql_alter and sql_table_maintenance -> sql_admin	2010-08-16 16:25:23 +02:00
Mattias Jonsson	4b20ccafaa	Bug#49907: ALTER TABLE ... TRUNCATE PARTITION does not wait for ... locks on the table Fixing the partitioning specifics after TRUNCATE TABLE in bug-42643 was fixed. Reorganize of code to decrease the size of the giant switch in mysql_execute_command, and to prepare for future parser reengineering. Moved code into Sql_statement objects. Updated patch according to davi's review comments. libmysqld/CMakeLists.txt: Added new files. libmysqld/Makefile.am: Added new files. mysql-test/r/not_partition.result: now returning error on partitioning commands if partitioning is not enabled. mysql-test/r/partition_disabled.result: There is no partition handlerton, so it cannot find the specified engine in the .frm file. mysql-test/r/partition_truncate.result: Updated test results. mysql-test/suite/parts/inc/partition_mgm.inc: Added check that TRUNCATE PARTITION does not delete on failure. mysql-test/suite/parts/r/partition_debug_sync_innodb.result: updated results. mysql-test/suite/parts/r/partition_mgm_lc0_archive.result: updated results. mysql-test/suite/parts/r/partition_mgm_lc1_archive.result: updated results. mysql-test/suite/parts/r/partition_mgm_lc2_archive.result: updated results. mysql-test/suite/parts/t/partition_debug_sync_innodb.test: Test case for this bug. mysql-test/t/not_partition.test: Added check for TRUNCATE PARTITION without partitioning. mysql-test/t/partition_truncate.test: Added test of TRUNCATE PARTITION on non partitioned table. sql/CMakeLists.txt: Added new files. sql/Makefile.am: Added new files. sql/datadict.cc: Moved out the storage engine check into an own function, including assert for lock. sql/datadict.h: added dd_frm_storage_engine. sql/sql_alter_table.cc: moved the code for SQLCOM_ALTER_TABLE in mysql_execute_command into its own file, and using the Sql_statement object to prepare for future parser reengineering. sql/sql_alter_table.h: Created Sql_statement object for ALTER TABLE. sql/sql_lex.cc: resetting m_stmt. sql/sql_lex.h: Temporary hack for forward declaration of enum_alter_table_change_level. sql/sql_parse.cc: Moved out ALTER/ANALYZE/CHECK/OPTIMIZE/REPAIR TABLE from the giant switch into their own Sql_statement objects. sql/sql_parse.h: Exporting check_merge_table_access. sql/sql_partition_admin.cc: created Sql_statement for ALTER TABLE t ANALYZE/CHECK/OPTIMIZE/REPAIR/TRUNCATE PARTITION. To be able to reuse the TABLE equivalents. sql/sql_partition_admin.h: Added Sql_statement of partition admin statements. sql/sql_table.cc: Moved table maintenance code into sql_table_maintenance.cc sql/sql_table.h: Moved table maintenance code into sql_table_maintenance.h exporting functions used by sql_table_maintenance. sql/sql_table_maintenance.cc: Moved table maintenance code from sql_table.cc sql/sql_table_maintenance.h: Sql_statement objects for ANALYZE/CHECK/OPTIMIZE/REPAIR TABLE. Also declaring the keycache functions. sql/sql_truncate.cc: Moved code from SQLCOM_TRUNCATE in mysql_execute_command into Truncate_statement::execute. Added check for partitioned table on TRUNCATE PARTITION. Moved locking fix for partitioned table into Alter_table_truncate_partition::execute. sql/sql_truncate.h: Truncate_statement declaration (sub class of Sql_statement). sql/sql_yacc.yy: Using the new Sql_statment objects.	2010-08-16 14:53:30 +02:00
Georgi Kodinov	9705711596	WL#1054: Pluggable authentication support ... Merged the implementation to a new base tree.	2010-08-09 11:32:50 +03:00
Dmitry Lenev	00496b7acd	Fix for bug #52044 "FLUSH TABLES WITH READ LOCK and FLUSH ... TABLES <list> WITH READ LOCK are incompatible". The problem was that FLUSH TABLES <list> WITH READ LOCK which was issued when other connection has acquired global read lock using FLUSH TABLES WITH READ LOCK was blocked and has to wait until global read lock is released. This issue stemmed from the fact that FLUSH TABLES <list> WITH READ LOCK implementation has acquired X metadata locks on tables to be flushed. Since these locks required acquiring of global IX lock this statement was incompatible with global read lock. This patch addresses problem by using SNW metadata type of lock for tables to be flushed by FLUSH TABLES <list> WITH READ LOCK. It is OK to acquire them without global IX lock as long as we won't try to upgrade those locks. Since SNW locks allow concurrent statements using same table FLUSH TABLE <list> WITH READ LOCK now has to wait until old versions of tables to be flushed go away after acquiring metadata locks. Since such waiting can lead to deadlock MDL deadlock detector was extended to take into account waits for flush and resolve such deadlocks. As a bonus code in open_tables() which was responsible for waiting old versions of tables to go away was refactored. Now when we encounter old version of table in open_table() we don't back-off and wait for all old version to go away, but instead wait for this particular table to be flushed. Such approach supported by deadlock detection should reduce number of scenarios in which FLUSH TABLES aborts concurrent multi-statement transactions. Note that active FLUSH TABLES <list> WITH READ LOCK still blocks concurrent FLUSH TABLES WITH READ LOCK statement as the former keeps tables open and thus prevents the latter statement from doing flush. mysql-test/include/handler.inc: Adjusted test case after changing status which is set when FLUSH TABLES waits for tables to be flushed from "Flushing tables" to "Waiting for table". mysql-test/r/flush.result: Added test which checks that "flush tables <list> with read lock" is compatible with active "flush tables with read lock" but not vice-versa. This test also covers bug #52044 "FLUSH TABLES WITH READ LOCK and FLUSH TABLES <list> WITH READ LOCK are incompatible". mysql-test/r/mdl_sync.result: Added scenarios in which wait for table to be flushed causes deadlocks to the coverage of MDL deadlock detector. mysql-test/suite/perfschema/r/dml_setup_instruments.result: Adjusted test results after removal of COND_refresh condition variable. mysql-test/suite/perfschema/r/server_init.result: Adjusted test and its results after removal of COND_refresh condition variable. mysql-test/suite/perfschema/t/server_init.test: Adjusted test and its results after removal of COND_refresh condition variable. mysql-test/t/flush.test: Added test which checks that "flush tables <list> with read lock" is compatible with active "flush tables with read lock" but not vice-versa. This test also covers bug #52044 "FLUSH TABLES WITH READ LOCK and FLUSH TABLES <list> WITH READ LOCK are incompatible". mysql-test/t/kill.test: Adjusted test case after changing status which is set when FLUSH TABLES waits for tables to be flushed from "Flushing tables" to "Waiting for table". mysql-test/t/lock_multi.test: Adjusted test case after changing status which is set when FLUSH TABLES waits for tables to be flushed from "Flushing tables" to "Waiting for table". mysql-test/t/mdl_sync.test: Added scenarios in which wait for table to be flushed causes deadlocks to the coverage of MDL deadlock detector. sql/ha_ndbcluster.cc: Adjusted code after adding one more parameter for close_cached_tables() call - timeout for waiting for table to be flushed. sql/ha_ndbcluster_binlog.cc: Adjusted code after adding one more parameter for close_cached_tables() call - timeout for waiting for table to be flushed. sql/lock.cc: Removed COND_refresh condition variable. See comment for sql_base.cc for details. sql/mdl.cc: Now MDL deadlock detector takes into account information about waits for table flushes when searching for deadlock. To implement this change: - Declaration of enum_deadlock_weight and Deadlock_detection_visitor were moved to mdl.h header to make them available to the code in table.cc which implements deadlock detector traversal through edges of waiters graph representing waiting for flush. - Since now MDL_context may wait not only for metadata lock but also for table to be flushed an abstract Wait_for_edge class was introduced. Its descendants MDL_ticket and Flush_ticket incapsulate specifics of inspecting waiters graph when following through edge representing wait of particular type. We no longer require global IX metadata lock when acquiring SNW or SNRW locks. Such locks are needed only when metadata locks of these types are upgraded to X locks. This allows to use SNW locks in FLUSH TABLES <list> WITH READ LOCK implementation and keep the latter compatible with global read lock. sql/mdl.h: Now MDL deadlock detector takes into account information about waits for table flushes when searching for deadlock. To implement this change: - Declaration of enum_deadlock_weight and Deadlock_detection_visitor were moved to mdl.h header to make them available to the code in table.cc which implements deadlock detector traversal through edges of waiters graph representing waiting for flush. - Since now MDL_context may wait not only for metadata lock but also for table to be flushed an abstract Wait_for_edge class was introduced. Its descendants MDL_ticket and Flush_ticket incapsulate specifics of inspecting waiters graph when following through edge representing wait of particular type. - Deadlock_detection_visitor now has m_table_shares_visited member which allows to support recursive locking for LOCK_open. This is required when deadlock detector inspects waiters graph which contains several edges representing waits for flushes or needs to come through the such edge more than once. sql/mysqld.cc: Removed COND_refresh condition variable. See comment for sql_base.cc for details. sql/mysqld.h: Removed COND_refresh condition variable. See comment for sql_base.cc for details. sql/sql_base.cc: Changed approach to how threads are waiting for table to be flushed. Now thread that wants to wait for old table to go away subscribes for notification by adding Flush_ticket to table's share and waits using MDL_context::m_wait object. Once table gets flushed (i.e. all tables are closed and table share is ready to be destroyed) all such waiters are notified individually. Thanks to this change MDL deadlock detector can take such waits into account. To implement this/as result of this change: - tdc_wait_for_old_versions() was replaced with tdc_wait_for_old_version() which waits for individual old share to go away and which is called by open_table() after finding out that share is outdated. We don't need to perform back-off before such waiting thanks to the fact that deadlock detector now sees such waits. - As result Open_table_ctx::m_mdl_requests became unnecessary and was removed. We no longer allocate copies of MDL_request objects on MEM_ROOT when MYSQL_OPEN_FORCE_SHARED/SHARED_HIGH_PRIO flags are in effect. - close_cached_tables() and tdc_wait_for_old_version() share code which implements waiting for share to be flushed - the both use TABLE_SHARE::wait_until_flush() method. Thanks to this close_cached_tables() supports timeouts and has extra parameter for this. - Open_table_context::OT_MDL_CONFLICT enum element was renamed to OT_CONFLICT as it is now also used in cases when back-off is required to resolve deadlock caused by waiting for flush and not metadata lock. - In cases when we discover that current connection tries to open tables from different generation we now simply back-off and restart process of opening tables. To support this Open_table_context::OT_REOPEN_TABLES enum element was added. - COND_refresh condition variable became unnecessary and was removed. - mysql_notify_thread_having_shared_lock() no longer wakes up connections waiting for flush as all such connections can be waken up by deadlock detector if necessary. sql/sql_base.h: - close_cached_tables() now has one more parameter - timeout for waiting for table to be flushed. - Open_table_context::OT_MDL_CONFLICT enum element was renamed to OT_CONFLICT as it is now also used in cases when back-off is required to resolve deadlock caused by waiting for flush and not metadata lock. Added new OT_REOPEN_TABLES enum element to be used in cases when we need to restart open tables process even in the middle of transaction. - Open_table_ctx::m_mdl_requests became unnecessary and was removed. sql/sql_class.h: Added assert ensuring that we won't use LOCK_open mutex with THD::enter_cond(). Otherwise deadlocks can arise in MDL deadlock detector. sql/sql_parse.cc: Changed FLUSH TABLES <list> WITH READ LOCK to take SNW metadata locks instead of X locks on tables to be flushed. Since we no longer require global IX lock to be taken when SNW locks are taken this makes this statement compatible with FLUSH TABLES WITH READ LOCK statement. Since SNW locks allow other connections to have table opened FLUSH TABLES <list> WITH READ LOCK now has to wait during open_tables() for old version to go away. Such waits can lead to deadlocks which will be detected by MDL deadlock detector which now takes waits for table to be flushed into account. Also adjusted code after adding one more parameter for close_cached_tables() call - timeout for waiting for table to be flushed. sql/sql_yacc.yy: FLUSH TABLES <list> WITH READ LOCK now needs only SNW metadata locks on tables. sql/sys_vars.cc: Adjusted code after adding one more parameter for close_cached_tables() call - timeout for waiting for table to be flushed. sql/table.cc: Implemented new approach to how threads are waiting for table to be flushed. Now thread that wants to wait for old table to go away subscribes for notification by adding Flush_ticket to table's share and waits using MDL_context::m_wait object. Once table gets flushed (i.e. all tables are closed and table share is ready to be destroyed) all such waiters are notified individually. This change allows to make such waits visible inside of MDL deadlock detector. To do it: - Added list of waiters/Flush_tickets to TABLE_SHARE class. - Changed free_table_share() to postpone freeing of share memory until last waiter goes away and to wake up subscribed waiters. - Added TABLE_SHARE::wait_until_flushed() method which implements subscription to the list of waiters for table to be flushed and waiting for this event. Implemented interface which allows to expose waits for flushes to MDL deadlock detector: - Introduced Flush_ticket class a descendant of Wait_for_edge class. - Added TABLE_SHARE::find_deadlock() method which allows deadlock detector to find out what contexts are still using old version of table in question (i.e. to find out what contexts are waited for by owner of Flush_ticket). sql/table.h: In order to support new strategy of waiting for table flush (see comment for table.cc for details) added list of waiters/Flush_tickets to TABLE_SHARE class. Implemented interface which allows to expose waits for flushes to MDL deadlock detector: - Introduced Flush_ticket class a descendant of Wait_for_edge class. - Added TABLE_SHARE::find_deadlock() method which allows deadlock detector to find out what contexts are still using old version of table in question (i.e. to find out what contexts are waited for by owner of Flush_ticket).	2010-07-27 17:34:58 +04:00
Jon Olav Hauglid	7467ee7bc6	merge from mysql-trunk-bugfixing	2010-07-19 10:27:53 +02:00
Davi Arnaut	1c924a1652	Merge of mysql-5.1-bugteam into mysql-trunk-merge.	2010-07-09 09:28:51 -03:00
Jon Olav Hauglid	9ff272fbbd	A 5.5 version of the fix for Bug #54360 "Deadlock DROP/ALTER/CREATE ... DATABASE with open HANDLER" Remove LOCK_create_db, database name locks, and use metadata locks instead. This exposes CREATE/DROP/ALTER DATABASE statements to the graph-based deadlock detector in MDL, and paves the way for a safe, deadlock-free implementation of RENAME DATABASE. Database DDL statements will now take exclusive metadata locks on the database name, while table/view/routine DDL statements take intention exclusive locks on the database name. This prevents race conditions between database DDL and table/view/routine DDL. (e.g. DROP DATABASE with concurrent CREATE/ALTER/DROP TABLE) By adding database name locks, this patch implements WL#4450 "DDL locking: CREATE/DROP DATABASE must use database locks" and WL#4985 "DDL locking: namespace/hierarchical locks". The patch also changes code to use init_one_table() where appropriate. The new lock_table_names() function requires TABLE_LIST::db_length to be set correctly, and this is taken care of by init_one_table(). This patch also adds a simple template to help work with the mysys HASH data structure. Most of the patch was written by Konstantin Osipov.	2010-07-01 15:53:46 +02:00
Konstantin Osipov	429454f76e	A new implementation for the TABLE_SHARE cache in MDL ... subsystem. Fix a number of caveates that the previous implementation suffered from, including unprotected access to shared data and lax resource accounting (share->ref_count) that could lead to deadlocks. The new implementation still suffers from a number of potential deadlocks in some edge cases, and this is still not enabled by default. Especially since performance testing has shown that it gives only marginable (not even exceeding measuring accuracy) improvements. @todo: - Remove calls to close_cached_tables() with REFRESH_FAST, and have_lock, because they break the MDL cache. - rework FLUSH TABLES <list> to not use close_cached_tables() - make sure that whenever we set TABLE_SHARE::version to 0 we free MDL cache references to it. sql/mdl.cc: We may cache references to TABLE_SHARE objects in MDL_lock objects for tables. Create a separate MDL_lock class to represent a table. sql/mdl.h: Adjust the MDL caching API to avoid races. sql/sql_base.cc: Move all caching functionality close together. Implement a solution for deadlocks caused by close_cached_tables() when MDL cache is enabled (incomplete). sql/sql_yacc.yy: Adjust FLUSH rule to do the necessary initialization of TABLE_LIST elements used in for FLUSH TABLES <list>, and thus work OK with flush_mdl_cache() function.	2010-06-18 20:14:10 +04:00
Konstantin Osipov	cc6dabba37	Merge trunk-bugfixing -> trunk-runtime	2010-06-17 17:31:51 +04:00
Davi Arnaut	db2fe44c84	Merge of mysql-5.1-bugteam into mysql-trunk-merge.	2010-06-10 22:30:49 -03:00
Davi Arnaut	0f9ddfa9d8	Bug#42733: Type-punning warnings when compiling MySQL -- ... strict aliasing violations. One somewhat major source of strict-aliasing violations and related warnings is the SQL_LIST structure. For example, consider its member function `link_in_list` which takes a pointer to pointer of type T (any type) as a pointer to pointer to unsigned char. Dereferencing this pointer, which is done to reset the next field, violates strict-aliasing rules and might cause problems for surrounding code that uses the next field of the object being added to the list. The solution is to use templates to parametrize the SQL_LIST structure in order to deference the pointers with compatible types. As a side bonus, it becomes possible to remove quite a few casts related to acessing data members of SQL_LIST. sql/handler.h: Use the appropriate template type argument. sql/item.cc: Remove now-unnecessary cast. sql/item_subselect.cc: Remove now-unnecessary casts. sql/item_sum.cc: Use the appropriate template type argument. Remove now-unnecessary cast. sql/mysql_priv.h: Move SQL_LIST structure to sql_list.h Use the appropriate template type argument. sql/sp.cc: Remove now-unnecessary casts. sql/sql_delete.cc: Use the appropriate template type argument. Remove now-unnecessary casts. sql/sql_derived.cc: Remove now-unnecessary casts. sql/sql_lex.cc: Remove now-unnecessary casts. sql/sql_lex.h: SQL_LIST now takes a template type argument which must match the type of the elements of the list. Use forward declaration when the type is not available, it is used in pointers anyway. sql/sql_list.h: Rename SQL_LIST to SQL_I_List. The template parameter is the type of object that is stored in the list. sql/sql_olap.cc: Remove now-unnecessary casts. sql/sql_parse.cc: Remove now-unnecessary casts. sql/sql_prepare.cc: Remove now-unnecessary casts. sql/sql_select.cc: Remove now-unnecessary casts. sql/sql_show.cc: Remove now-unnecessary casts. sql/sql_table.cc: Remove now-unnecessary casts. sql/sql_trigger.cc: Remove now-unnecessary casts. sql/sql_union.cc: Remove now-unnecessary casts. sql/sql_update.cc: Remove now-unnecessary casts. sql/sql_view.cc: Remove now-unnecessary casts. sql/sql_yacc.yy: Remove now-unnecessary casts. storage/myisammrg/ha_myisammrg.cc: Remove now-unnecessary casts.	2010-06-10 17:45:22 -03:00
Magne Mahre	db716d11af	Bug#20837 Apparent change of isolation level during transaction ... Bug#46527 COMMIT AND CHAIN RELEASE does not make sense Bug#53343 completion_type=1, COMMIT/ROLLBACK AND CHAIN don't preserve the isolation level Bug#53346 completion_type has strange effect in a stored procedure/prepared statement Added test cases to verify the expected behaviour of : SET SESSION TRANSACTION ISOLATION LEVEL, SET TRANSACTION ISOLATION LEVEL, @@completion_type, COMMIT AND CHAIN, ROLLBACK AND CHAIN ..and some combinations of the above	2010-06-08 19:47:10 +02:00
Jon Olav Hauglid	4ea99a50be	Bug #54282 Crash in MDL_context::upgrade_shared_lock_to_exclusive ... This crash happened if a table was listed twice in a DROP TABLE statement, and the statement was executed while in LOCK TABLES mode. Since the two elements of table list were identical, they were assigned the same TABLE object. During processing of the first table element, the TABLE instance was destroyed and the second table list element was left with a dangling reference. When this reference was later accessed, the server crashed. Listing the same table twice in DROP TABLES should give an ER_NONUNIQ_TABLE error. However, this did not happen as the check for unique table names was skipped due to the lock type for table list elements being set to TL_IGNORE. Previously TL_UNLOCK was used and the unique check was performed. This bug was a regression introduced by a pre-requisite patch for Bug#51263 "Deadlock between transactional SELECT and ALTER TABLE ... REBUILD PARTITION". The regression only existed in an internal team tree and never in any released code. This patch reverts DROP TABLE (and DROP VIEW) to the old behavior of using TL_UNLOCK locks. Test case added to drop.test.	2010-06-07 17:27:40 +02:00
Jon Olav Hauglid	142a162c66	manual merge from mysql-trunk-bugfixing ... Conflicts: Text conflict in mysql-test/r/archive.result Contents conflict in mysql-test/r/innodb_bug38231.result Text conflict in mysql-test/r/mdl_sync.result Text conflict in mysql-test/suite/binlog/t/disabled.def Text conflict in mysql-test/suite/rpl_ndb/r/rpl_ndb_binlog_format_errors.result Text conflict in mysql-test/t/archive.test Contents conflict in mysql-test/t/innodb_bug38231.test Text conflict in mysql-test/t/mdl_sync.test Text conflict in sql/sp_head.cc Text conflict in sql/sql_show.cc Text conflict in sql/table.cc Text conflict in sql/table.h	2010-06-06 13:19:29 +02:00
Alexander Nozdrin	59a9912963	Auto-merge from mysql-trunk.	2010-05-28 09:47:58 +04:00
Dmitry Lenev	ae1ae4bd63	Fix for bug #51263 "Deadlock between transactional ... SELECT and ALTER TABLE ... REBUILD PARTITION". ALTER TABLE on InnoDB table (including partitioned tables) acquired exclusive locks on rows of table being altered. In cases when there was concurrent transaction which did locking reads from this table this sometimes led to a deadlock which was not detected by MDL subsystem nor by InnoDB engine (and was reported only after exceeding innodb_lock_wait_timeout). This problem stemmed from the fact that ALTER TABLE acquired TL_WRITE_ALLOW_READ lock on table being altered. This lock was interpreted as a write lock and thus for table being altered handler::external_lock() method was called with F_WRLCK as an argument. As result InnoDB engine treated ALTER TABLE as an operation which is going to change data and acquired LOCK_X locks on rows being read from old version of table. In case when there was a transaction which already acquired SR metadata lock on table and some LOCK_S locks on its rows (e.g. by using it in subquery of DML statement) concurrent ALTER TABLE was blocked at the moment when it tried to acquire LOCK_X lock before reading one of these rows. The transaction's attempt to acquire SW metadata lock on table being altered led to deadlock, since it had to wait for ALTER TABLE to release SNW lock. This deadlock was not detected and got resolved only after timeout expiring because waiting were happening in two different subsystems. Similar deadlocks could have occured in other situations. This patch tries to solve the problem by changing ALTER TABLE implementation to use TL_READ_NO_INSERT lock instead of TL_WRITE_ALLOW_READ. After this step handler::external_lock() is called with F_RDLCK as an argument and InnoDB engine correctly interprets ALTER TABLE as operation which only reads data from original version of table. Thanks to this ALTER TABLE acquires only LOCK_S locks on rows it reads. This, in its turn, causes inter-subsystem deadlocks to go away, as all potential lock conflicts and thus deadlocks will be limited to metadata locking subsystem: - When ALTER TABLE reads rows from table being altered it can't encounter any locks which conflict with LOCK_S row locks. There should be no concurrent transactions holding LOCK_X row locks. Such a transaction should have been acquired SW metadata lock on table first which would have conflicted with ALTER's SNW lock. - Vice versa, when DML which runs concurrently with ALTER TABLE tries to lock row it should be requesting only LOCK_S lock which is compatible with locks acquired by ALTER, as otherwise such DML must own an SW metadata lock on table which would be incompatible with ALTER's SNW lock. mysql-test/r/innodb_mysql_lock2.result: Added test for bug #51263 "Deadlock between transactional SELECT and ALTER TABLE ... REBUILD PARTITION". mysql-test/suite/rpl_ndb/r/rpl_ndb_binlog_format_errors.result: Since CREATE TRIGGER no longer acquires write lock on table it is no longer interpreted as an operation which modifies table data and therefore no longer fails if invoked for SBR-only engine in ROW mode. mysql-test/suite/rpl_ndb/t/rpl_ndb_binlog_format_errors.test: Since CREATE TRIGGER no longer acquires write lock on table it is no longer interpreted as an operation which modifies table data and therefore no longer fails if invoked for SBR-only engine in ROW mode. mysql-test/t/innodb_mysql_lock2.test: Added test for bug #51263 "Deadlock between transactional SELECT and ALTER TABLE ... REBUILD PARTITION". sql/ha_partition.cc: When ALTER TABLE creates a new partition to be filled from other partition lock it in F_WRLCK mode instead of using mode which was used for locking the whole table (it is F_RDLCK now). sql/lock.cc: Replaced conditions which used TL_WRITE_ALLOW_READ lock type with equivalent conditions using TL_WRITE_ALLOW_WRITE. This should allow to get rid of TL_WRITE_ALLOW_READ lock type eventually. sql/mdl.cc: Updated outdated comment to reflect current situation. sql/sql_base.cc: Replaced conditions which used TL_WRITE_ALLOW_READ lock type with equivalent conditions using TL_WRITE_ALLOW_WRITE. This should allow to get rid of TL_WRITE_ALLOW_READ lock type eventually. sql/sql_table.cc: mysql_admin_table(): Use TL_WRITE_ALLOW_WRITE lock type instead of TL_WRITE_ALLOW_READ to determine that we need to acquire upgradable metadata lock. This should allow to completely get rid of TL_WRITE_ALLOW_READ in long term. mysql_recreate_table(): ALTER TABLE now requires TL_READ_NO_INSERT thr_lock.c lock instead of TL_WRITE_ALLOW_READ. sql/sql_trigger.cc: Changed CREATE/DROP TRIGGER implementation to use TL_READ_NO_INSERT lock instead of TL_WRITE_ALLOW_READ lock. The latter is no longer necessary since: a) We now can rely on metadata locks to achieve proper isolation between two DDL statements or DDL and DML statements. b) This statement does not change any data in table so there is no need to inform storage engine about it. sql/sql_yacc.yy: Changed implementation of ALTER TABLE (and CREATE/DROP INDEX as a consequence) to use TL_READ_NO_INSERT lock instead of TL_WRITE_ALLOW_READ lock. This is possible since: a) We now can rely on metadata locks to achieve proper isolation between two DDL statements or DDL and DML statements. b) This statement only reads data in table being open. We write data only to the new version of table and then replace with it old version of table under X metadata lock. Thanks to this change InnoDB will no longer acquire LOCK_X locks on rows being read by ALTER TABLE (instead LOCK_S locks will be acquired) and thus cause of bug #51263 "Deadlock between transactional SELECT and ALTER TABLE ... REBUILD PARTITION" is removed. Did the similar change for CREATE TRIGGER (see comments for sql_trigger.cc for details).	2010-05-26 16:18:08 +04:00
Davi Arnaut	4f18083b08	Bug#42643: InnoDB does not support replication of TRUNCATE TABLE ... The problem was that TRUNCATE TABLE didn't take a exclusive lock on a table if it resorted to truncating via delete of all rows in the table. Specifically for InnoDB tables, this could break proper isolation as InnoDB ends up aborting some granted locks when truncating a table. The solution is to take a exclusive metadata lock before TRUNCATE TABLE can proceed. This guarantees that no other transaction is using the table. Incompatible change: Truncate via delete no longer fails if sql_safe_updates is activated (this was a undocumented side effect). libmysqld/CMakeLists.txt: Add new files to the build list. libmysqld/Makefile.am: Add new files to the build list. mysql-test/extra/binlog_tests/binlog_truncate.test: Add test case for Bug#42643 mysql-test/include/mix1.inc: Update test case as TRUNCATE TABLE now grabs a exclusive lock. Ensure that TRUNCATE waits for granted locks on the table. mysql-test/suite/binlog/t/binlog_truncate_innodb.test: As with other data modifying statements, TRUNCATE is still not possible in a transaction with isolation level READ COMMITTED or READ UNCOMMITED. It would be possible to implement so, but it is not worth the effort. mysql-test/suite/binlog/t/binlog_truncate_myisam.test: Test under different binlog formats. mysql-test/suite/binlog/t/disabled.def: Re-enable test case. mysql-test/t/innodb_bug38231.test: Truncate no longer works with row-level locks. mysql-test/t/mdl_sync.test: Ensure that a acquired lock is not given up due to a conflict. mysql-test/t/partition_innodb_semi_consistent.test: End transaction as to release metadata locks. mysql-test/t/truncate.test: A metadata lock is now taken before the object is verified. sql/CMakeLists.txt: Add new files to the build list. sql/Makefile.am: Add new files to the build list. sql/datadict.cc: Introduce a new file specific for data dictionary operations. sql/datadict.h: Add header file. sql/sql_base.cc: Rename data dictionary function. sql/sql_bitmap.h: Include dependency. sql/sql_delete.cc: Move away from relying on mysql_delete() to delete all rows of a table. Thus, move any bits related to truncate to sql_truncate.cc sql/sql_delete.h: Remove parameter. sql/sql_parse.cc: Add protection against the global read lock -- a intention exclusive lock can be acquired in the truncate path. sql/sql_show.cc: Add sync point for testing scenarios where a pending flush is ignored. sql/sql_truncate.cc: Acquire a shared metadata lock before accessing table metadata. Upgrade the lock to a exclusive one if the table can be re-created. Rework binlog rules to better reflect the requirements. sql/sql_yacc.yy: Set appropriate lock types for table to be truncated. sql/table.h: Move to data dictionary header.	2010-05-25 17:01:38 -03:00
Dmitry Lenev	bee0f214fd	Pre-requisite patch for bug #51263 "Deadlock between ... transactional SELECT and ALTER TABLE ... REBUILD PARTITION". The goal of this patch is to decouple type of metadata lock acquired for table by open_tables() from type of table-level lock to be acquired on it. To achieve this we change approach to how we determine what type of metadata lock should be acquired on table to be open. Now instead of inferring it at open_tables() time from flags and type of table-level lock we rely on that type of metadata lock is properly set at parsing time and is not changed further. sql/ha_ndbcluster.cc: Now one needs to properly initialize table list element's MDL_request object before calling mysql_rm_table_part2(). sql/lock.cc: lock_table_names() no longer initializes table list elements' MDL_request objects. Now proper initialization of these requests is a responsibility of the caller. sql/lock.h: Removed MYSQL_OPEN_TAKE_UPGRADABLE_MDL flag which became unnecessary. Thanks to the fact that we don't reset type of requests for metadata locks between re-executions we now can figure out that upgradable locks are requested by simply looking at their type which were set in the parser. As result this flag became redundant. sql/mdl.h: Added version of new operator which simplifies allocation of MDL_request objects on a MEM_ROOT. sql/sp_head.cc: Added comment explaining why it is OK to infer type of metadata lock to request from type of table-level lock for prelocking. Added enum_mdl_type argument to sp_add_to_query_tables() to simplify its usage in trigger implementation. sql/sp_head.h: Added enum_mdl_type argument to sp_add_to_query_tables() to simplify its usage in trigger implementation. sql/sql_base.cc: - open_table_get_mdl_lock(): Preserve type of MDL_request for table list element which was set in the parser by creating MDL_request objects on memory root if MYSQL_OPEN_FORCE_SHARED_MDL or MYSQL_OPEN_FORCE_SHARED_HIGH_PRIO_MDL flag were specified. Thanks to this and to the fact that we no longer reset type of requests for metadata locks between re-executions we no longer need to acquire exclusive metadata lock on table to be created in a special way. This lock is acquired by code handling acquiring of upgradable locks. Also changed signature/calling convention for this function to simplify its usage. - Accordingly special lock strategy for table list elements which was used for such locks became unnecessary and was removed. Other strategies were renamed. - Since we no longer have guarantee that MDL_request object which were not satisfied due to lock conflict belongs to table list element Open_table_context class and its methods were extended to remember pointer to MDL_request which has caused problem at request_backoff_action() time and use it in recover_from_failed_open(). Similar approach is used for cases when problem from which we need to recover is not related to MDL but to the table itself. In this case we store pointer to the element of table list. - Changed open_tables()/open_tables_check_upgradable_mdl()/ open_tables_acquire_upgradable_mdl() not to rely on MYSQL_OPEN_TAKE_UPGRADABLE_MDL flag to understand when upgradable metadata locks should be acquired and not to infer type of MDL lock from type of table-level lock. Instead we assume that type of MDL to be acquired was set in the parser (we can do this as type of MDL_request is no longer reset between re-executions). sql/sql_class.h: Since we no longer have guarantee that MDL_request object which were not satisfied due to lock conflict belongs to table list element Open_table_context class and its methods were extended to remember pointer to MDL_request which has caused problem at request_backoff_action() time and use it in recover_from_failed_open(). Similar approach is used for cases when problem from which we need to recover is not related to MDL but to the table itself. In this case we store pointer to the element of table list. sql/sql_db.cc: Now one needs to properly initialize table list element's MDL_request object before calling mysql_rm_table_part2() or mysql_rename_tables(). sql/sql_lex.cc: st_select_lex/st_select_lex_node::add_table_to_list() method now has argument which allows specify type of metadata lock to be requested for table list element being added. sql/sql_lex.h: - st_select_lex/st_select_lex_node::add_table_to_list() method now has argument which specifies type of metadata lock to be requested for table list element being added. This allows to explicitly set type of MDL lock to be acquired for a DDL statement in parser. It is also more future-proof than inferring type of MDL request from type of table-level lock. - Added Yacc_state::m_mdl_type member which specifies which type of metadata lock should be requested for tables to be added to table list by a grammar rule in cases when the same rule is used in several statements requiring different kinds of metadata locks. sql/sql_parse.cc: - st_select_lex::add_table_to_list() method now has argument which specifies type of metadata lock to be requested for table list element being added. This allows to explicitly set type of MDL lock to be acquired for a DDL statement in parser. It is also more future-proof than inferring type of MDL request from type of table-level lock. - EXCLUSIVE_DOWNGRADABLE_MDL lock strategy has a new name - OTLS_DOWNGRADE_IF_EXISTS. - Adjusted LOCK TABLES implementation to the fact that we no longer infer type of metadata lock to be acquired from table level lock and that type of MDL request is set at parsing. And thus MYSQL_OPEN_TAKE_UPGRADABLE_MDL flag became unnecessary. sql/sql_prepare.cc: TABLE_LIST's lock strategy SHARED_MDL was renamed to OTLS_NONE as now it means that metadata lock should not be changed during call to open_table() (if it has been already acquired) and is also used for exclusive metadata lock. sql/sql_show.cc: st_select_lex::add_table_to_list() method now has argument which specifies type of metadata lock to be requested for table list element being added. sql/sql_table.cc: - Adjusted mysql_admin_table()'s code to the fact that open_tables() no longer determines what kind of metadata lock should be obtained basing on type of table-level lock and flags. Instead type of metadata lock for table to be open should be set before calling open_tables(). - Changed mysql_alter_table() code to the facts: a) that now it is responsibility of caller to properly initalize MDL_request in table list elements before calling lock_table_names() b) and that MYSQL_OPEN_TAKE_UPGRADABLE_MDL is no longer necessary since type of metadata lock to be obtained at open_tables() time is set during parsing. - Changed code of mysql_recreate_table() to properly set type of metadata and table-level lock to be obtained by mysql_alter_table() which it calls. sql/sql_trigger.cc: Instead of relying on MYSQL_OPEN_TAKE_UPGRADABLE_MDL flag to force open_tables() to take an upgradable lock we now specify exact type of lock to be taken when constructing table list element for table to be open for CREATE/DROP TRIGGER. sql/sql_view.cc: We no longer use TABLE_LIST::EXCLUSIVE_MDL strategy to force open_tables() to take an exclusive metadata lock on view to be created. Instead we rely on parser setting proper type of metadata lock to request and open_tables() acquiring it. This became possible thanks to the fact that we no longer reset type of MDL_request between statement re-executions. sql/sql_yacc.yy: Instead of inferring type of MDL_request for table to be open from type of table-level lock and flags passed to open_tables() we now explicitly specify them at parsing. This became possible thanks to the fact that we no longer reset type of MDL_request between statement re-executions. In future this should allow to decouple type of metadata lock from type of table-level lock. The only exception to this approach is statements implemented through mysql_admin_table() which re-uses same table list element several times with different types of table-level and metadata locks. We now also properly initialize MDL_request objects for table list elements which are later passed to lock_table_names() function. sql/table.cc: Do not reset type of MDL_request between statement re-executions. This became unnecessesary as we no longer change type of MDL_request residing in table list element. In its turn this change allows to set type of MDL_request only once - at parsing time. sql/table.h: Got rid of TABLE_LIST::EXCLUSIVE_MDL lock strategy. Now we can specify that we need to acquire exclusive lock on table to be processed by open_tables() through setting an appropriate type of MDL_request at parsing time (this became possible thanks to the fact that we no longer reset types of MDL_request's belonging to table list elements between statement re-execution). Strategy SHARED_MDL was renamed to OTLS_NONE as now it means that metadata lock should not be changed during call to open_table() (if it has been already acquired) and is also used for exclusive metadata lock. Strategy EXCLUSIVE_DOWNGRADABLE_MDL was renamed to OTLS_DOWNGRADE_IF_EXISTS.	2010-05-25 16:35:01 +04:00
Alexey Kopytov	5ef2bdea81	Manual merge of mysql-5.1-bugteam to mysql-trunk-merge. ... Conflicts: Text conflict in mysql-test/r/grant.result Text conflict in mysql-test/t/grant.test Text conflict in mysys/mf_loadpath.c Text conflict in sql/slave.cc Text conflict in sql/sql_priv.h	2010-05-09 02:03:35 +04:00
Konstantin Osipov	946fad3502	Draft patch that fixes and a sketches test cases for: ... Bug#20837 Apparent change of isolation level during transaction, Bug#46527 COMMIT AND CHAIN RELEASE does not make sense, Bug#53343 completion_type=1, COMMIT/ROLLBACK AND CHAIN don't preserve the isolation level Bug#53346 completion_type has strange effect in a stored procedure/prepared statement Make thd->tx_isolation mean strictly "current transaction isolation level" Make thd->variables.tx_isolation mean "current session isolation level". The current transaction isolation level is now established at transaction start. If there was a SET TRANSACTION ISOLATION LEVEL statement, the value is taken from it. Otherwise, the session value is used. A change in a session value, made while a transaction is active, whereas still allowed, no longer has any effect on the current transaction isolation level. This is an incompatible change. A change in a session isolation level, made while there is no active transaction, overrides SET TRANSACTION statement, if there was any. Changed the impelmentation to not look at @@session.completion_type in the parser, and thus fixed Bug#53346. Changed the parser to not allow AND NO CHAIN RELEASE, and thus fixed Bug#46527. Changed the transaction API to take the current transaction isolation level into account: - BEGIN/COMMIT now do preserve the current transaction isolation level if chaining is on. - implicit commit, XA COMMIT or XA ROLLBACK or autocommit don't.	2010-05-07 20:28:59 +04:00
Georgi Kodinov	71b453fa06	Bug #53371: COM_FIELD_LIST can be abused to bypass table level grants. ... This is the 5.1 merge and extension of the fix. The server was happily accepting paths in table name in all places a table name is accepted (e.g. a SELECT). This allowed all users that have some privilege over some database to read all tables in all databases in all mysql server instances that the server file system has access to. Fixed by : 1. making sure no path elements are allowed in quoted table name when constructing the path (note that the path symbols are still valid in table names when they're properly escaped by the server). 2. checking the #mysql50# prefixed names the same way they're checked for path elements in mysql-5.0.	2010-05-04 17:03:28 +03:00
Konstantin Osipov	1ab519d91f	Committing on behalf or Dmitry Lenev: ... Fix for bug #46947 "Embedded SELECT without FOR UPDATE is causing a lock", with after-review fixes. SELECT statements with subqueries referencing InnoDB tables were acquiring shared locks on rows in these tables when they were executed in REPEATABLE-READ mode and with statement or mixed mode binary logging turned on. This was a regression which were introduced when fixing bug 39843. The problem was that for tables belonging to subqueries parser set TL_READ_DEFAULT as a lock type. In cases when statement/mixed binary logging at open_tables() time this type of lock was converted to TL_READ_NO_INSERT lock at open_tables() time and caused InnoDB engine to acquire shared locks on reads from these tables. Although in some cases such behavior was correct (e.g. for subqueries in DELETE) in case of SELECT it has caused unnecessary locking. This patch tries to solve this problem by rethinking our approach to how we handle locking for SELECT and subqueries. Now we always set TL_READ_DEFAULT lock type for all cases when we read data. When at open_tables() time this lock is interpreted as TL_READ_NO_INSERT or TL_READ depending on whether this statement as a whole or call to function which uses particular table should be written to the binary log or not (if yes then statement should be properly serialized with concurrent statements and stronger lock should be acquired). Test coverage is added for both InnoDB and MyISAM. This patch introduces an "incompatible" change in locking scheme for subqueries used in SELECT ... FOR UPDATE and SELECT .. IN SHARE MODE. In 4.1 the server would use a snapshot InnoDB read for subqueries in SELECT FOR UPDATE and SELECT .. IN SHARE MODE statements, regardless of whether the binary log is on or off. If the user required a different type of read (i.e. locking read), he/she could request so explicitly by providing FOR UPDATE/IN SHARE MODE clause for each individual subquery. On of the patches for 5.0 broke this behaviour (which was not documented or tested), and started to use locking reads fora all subqueries in SELECT ... FOR UPDATE/IN SHARE MODE. This patch restored 4.1 behaviour. mysql-test/include/check_concurrent_insert.inc: Added auxiliary script which allows to check if statement reading table allows concurrent inserts in it. mysql-test/include/check_no_concurrent_insert.inc: Added auxiliary script which allows to check that statement reading table doesn't allow concurrent inserts in it. mysql-test/include/check_no_row_lock.inc: Added auxiliary script which allows to check if statement reading table doesn't take locks on its rows. mysql-test/include/check_shared_row_lock.inc: Added auxiliary script which allows to check if statement reading table takes shared locks on some of its rows. mysql-test/r/bug39022.result: After bug #46947 'Embedded SELECT without FOR UPDATE is causing a lock' was fixed test case for bug 39022 has to be adjusted in order to trigger execution path on which original problem was encountered. mysql-test/r/innodb_mysql_lock2.result: Added coverage for handling of locking in various cases when we read data from InnoDB tables (includes test case for bug #46947 'Embedded SELECT without FOR UPDATE is causing a lock'). mysql-test/r/lock_sync.result: Added coverage for handling of locking in various cases when we read data from MyISAM tables. mysql-test/t/bug39022.test: After bug #46947 'Embedded SELECT without FOR UPDATE is causing a lock' was fixed test case for bug 39022 has to be adjusted in order to trigger execution path on which original problem was encountered. mysql-test/t/innodb_mysql_lock2.test: Added coverage for handling of locking in various cases when we read data from InnoDB tables (includes test case for bug #46947 'Embedded SELECT without FOR UPDATE is causing a lock'). mysql-test/t/lock_sync.test: Added coverage for handling of locking in various cases when we read data from MyISAM tables. sql/log_event.cc: Since LEX::lock_option member was removed we no longer can rely on its value in Load_log_event::print_query() to determine that log event correponds to LOAD DATA CONCURRENT statement (this was not correct in all situations anyway). A new Load_log_event's member was introduced as a replacement. It is initialized at event object construction time and explicitly indicates whether LOAD DATA was concurrent. sql/log_event.h: Since LEX::lock_option member was removed we no longer can rely on its value in Load_log_event::print_query() to determine that log event correponds to LOAD DATA CONCURRENT statement (this was not correct in all situations anyway). A new Load_log_event's member was introduced as a replacement. It is initialized at event object construction time and explicitly indicates whether LOAD DATA was concurrent. sql/sp_head.cc: sp_head::reset_lex(): Before parsing substatement reset part of parser state which needs this (e.g. set Yacc_state::m_lock_type to default value). sql/sql_acl.cc: Since LEX::reset_n_backup_query_tables_list() now also resets LEX::sql_command member (as it became part of Query_tables_list class) we have to restore it in cases when while working with proxy Query_table_list we assume that LEX::sql_command still corresponds to original SQL command being executed (for example, when we are logging statement to the binary log while having Query_tables_list reset and backed up). sql/sql_base.cc: Changed read_lock_type_for_table() to return a weak TL_READ type of lock in cases when we are executing statement which won't update tables directly and table doesn't belong to statement's prelocking list and thus can't be used by a stored function. It is OK to do so since in this case table won't be used by statement or function call which will be written to the binary log, so serializability requirements for it can be relaxed. One of results from this change is that SELECTs on InnoDB tables no longer takes shared row locks for tables which are used in subqueries (i.e. bug #46947 is fixed). Another result is that for similar SELECTs on MyISAM tables concurrent inserts are allowed. In order to implement this change signature of read_lock_type_for_table() function was changed to take pointers to Query_tables_list and TABLE_LIST objects. sql/sql_base.h: - Function read_lock_type_for_table() now takes pointers to Query_tables_list and TABLE_LIST elements as its arguments since to correctly determine lock type it needs to know what statement is being performed and whether table element for which lock type to be determined belongs to prelocking list. sql/sql_lex.cc: - Removed LEX::lock_option and st_select_lex::lock_option members. Places in parser that were using them now use Yacc_state::m_lock_type instead. - To emphasize that LEX::sql_command member is used during process of opening and locking of tables it was moved to Query_tables_list class. It is now reset by Query_tables_list::reset_query_tables_list() method. sql/sql_lex.h: - Removed st_select_lex::lock_option member as there is no real need for per-SELECT lock type (HIGH_PRIORITY option should apply to the whole statement. FOR UPDATE/LOCK IN SHARE MODE clauses can be handled without this member). The main effect which was achieved by introduction of this member, i.e. using TL_READ_DEFAULT lock type for subqueries, is now achieved by setting LEX::lock_option (or rather its replacement - Yacc_state::m_lock_type) to TL_READ_DEFAULT in almost all cases. - To emphasize that LEX::sql_command member is used during process of opening and locking of tables it was moved to Query_tables_list class. - Replaced LEX::lock_option with Yacc_state::m_lock_type in order to emphasize that this value is relevant only during parsing. Unlike for LEX::lock_option the default value for Yacc_state::m_lock_type is TL_READ_DEFAULT. Note that for cases when it is OK to take a "weak" read lock (e.g. simple SELECT) this lock type will be converted to TL_READ at open_tables() time. So this change won't cause negative change in behavior for such statements. OTOH this change ensures that, for example, for SELECTs which are used in stored functions TL_READ_NO_INSERT lock is taken when necessary and as result calls to such stored functions can be written to the binary log with correct serialization. sql/sql_load.cc: Load_log_event constructor now requires a parameter that indicates whether LOAD DATA is concurrent. sql/sql_parse.cc: LEX::lock_option was replaced with Yacc_state::m_lock_type. And instead of resetting the latter implicitly in mysql_init_multi_delete() we do it explicitly in the places in parser which call this function. sql/sql_priv.h: - To be able more easily distinguish high-priority SELECTs in st_select_lex::print() method added flag for HIGH_PRIORITY option. sql/sql_select.cc: Changed code not to rely on LEX::lock_option to determine that it is high-priority SELECT. It was replaced with Yacc_state::m_lock_type which is accessible only at parse time. So instead of LEX::lock_option we now rely on a newly introduced flag for st_select_lex::options - SELECT_HIGH_PRIORITY. sql/sql_show.cc: Since LEX::reset_n_backup_query_tables_list() now also resets LEX::sql_command member (as it became part of Query_tables_list class) we have to restore it in cases when while working with proxy Query_table_list we assume that LEX::sql_command still corresponds to original SQL command being executed. sql/sql_table.cc: Since LEX::reset_query_tables_list() now also resets LEX::sql_command member (as it became part of Query_tables_list class) we have to restore value of this member when this method is called by mysql_admin_table(), to make this code safe for re-execution. sql/sql_trigger.cc: Since LEX::reset_n_backup_query_tables_list() now also resets LEX::sql_command member (as it became part of Query_tables_list class) we have to restore it in cases when while working with proxy Query_table_list we assume that LEX::sql_command still corresponds to original SQL command being executed (for example, when we are logging statement to the binary log while having Query_tables_list reset and backed up). sql/sql_update.cc: Function read_lock_type_for_table() now takes pointers to Query_tables_list and TABLE_LIST elements as its arguments since to correctly determine lock type it needs to know what statement is being performed and whether table element for which lock type to be determined belongs to prelocking list. sql/sql_yacc.yy: - Removed st_select_lex::lock_option member as there is no real need for per-SELECT lock type (HIGH_PRIORITY option should apply to the whole statement. FOR UPDATE/LOCK IN SHARE MODE clauses can be handled without this member). The main effect which was achieved by introduction of this member, i.e. using TL_READ_DEFAULT lock type for subqueries, is now achieved by setting LEX::lock_option (or rather its replacement - Yacc_state::m_lock_type) to TL_READ_DEFAULT in almost all cases. - Replaced LEX::lock_option with Yacc_state::m_lock_type in order to emphasize that this value is relevant only during parsing. Unlike for LEX::lock_option the default value for Yacc_state::m_lock_type is TL_READ_DEFAULT. Note that for cases when it is OK to take a "weak" read lock (e.g. simple SELECT) this lock type will be converted to TL_READ at open_tables() time. So this change won't cause negative change in behavior for such statements. OTOH this change ensures that, for example, for SELECTs which are used in stored functions TL_READ_NO_INSERT lock is taken when necessary and as result calls to such stored functions can be written to the binary log with correct serialization. - To be able more easily distinguish high-priority SELECTs in st_select_lex::print() method we now use new flag in st_select_lex::options bit-field.	2010-04-28 14:04:11 +04:00
Konstantin Osipov	4288e329dd	A fix for Bug#11918 "SP does not accept variables in LIMIT clause" ... Allow stored procedure variables in LIMIT clause. Only allow variables of INTEGER types. Handle negative values by means of an implicit cast to UNSIGNED (similarly to prepared statement placeholders). Add tests. Make sure replication works by not doing NAME_CONST substitution for variables in LIMIT clause. Add replication tests. mysql-test/r/sp.result: Update results (Bug#11918). mysql-test/suite/rpl/r/rpl_sp.result: Update results (Bug#11918). mysql-test/suite/rpl/t/rpl_sp.test: Add a test case for Bug#11918. mysql-test/t/sp.test: Add a test case for Bug#11918. sql/item.cc: Mark sp variables in LIMIT clause (a hack for replication). sql/item.h: Mark sp variables in LIMIT clause (a hack for replication). sql/share/errmsg-utf8.txt: Add a new error message (a type mismatch for LIMIT clause parameter). sql/sp_head.cc: Binlog rewrite sp variables in LIMIT clause without NAME_CONST substitution. sql/sql_string.cc: Implement append_ulonglong method. sql/sql_string.h: Declare append_ulonglong(). sql/sql_yacc.yy: Support stored procedure variables in LIMIT.	2010-04-14 01:56:19 +04:00
Mats Kindahl	23d8586dbf	WL#5030: Split and remove mysql_priv.h ... This patch: - Moves all definitions from the mysql_priv.h file into header files for the component where the variable is defined - Creates header files if the component lacks one - Eliminates all include directives from mysql_priv.h - Eliminates all circular include cycles - Rename time.cc to sql_time.cc - Rename mysql_priv.h to sql_priv.h	2010-03-31 16:05:33 +02:00
Alexey Kopytov	d95c1e3b47	Manual merge of mysql-trunk into mysql-trunk-merge. ... Conflicts: Text conflict in client/mysqlbinlog.cc Text conflict in mysql-test/Makefile.am Text conflict in mysql-test/collections/default.daily Text conflict in mysql-test/r/mysqlbinlog_row_innodb.result Text conflict in mysql-test/suite/rpl/r/rpl_typeconv_innodb.result Text conflict in mysql-test/suite/rpl/t/rpl_get_master_version_and_clock.test Text conflict in mysql-test/suite/rpl/t/rpl_row_create_table.test Text conflict in mysql-test/suite/rpl/t/rpl_slave_skip.test Text conflict in mysql-test/suite/rpl/t/rpl_typeconv_innodb.test Text conflict in mysys/charset.c Text conflict in sql/field.cc Text conflict in sql/field.h Text conflict in sql/item.h Text conflict in sql/item_func.cc Text conflict in sql/log.cc Text conflict in sql/log_event.cc Text conflict in sql/log_event_old.cc Text conflict in sql/mysqld.cc Text conflict in sql/rpl_utility.cc Text conflict in sql/rpl_utility.h Text conflict in sql/set_var.cc Text conflict in sql/share/Makefile.am Text conflict in sql/sql_delete.cc Text conflict in sql/sql_plugin.cc Text conflict in sql/sql_select.cc Text conflict in sql/sql_table.cc Text conflict in storage/example/ha_example.h Text conflict in storage/federated/ha_federated.cc Text conflict in storage/myisammrg/ha_myisammrg.cc Text conflict in storage/myisammrg/myrg_open.c	2010-03-24 18:03:44 +03:00
Alexey Kopytov	5d407d0c1a	Manual merge of mysql-5.1-bugteam to mysql-trunk-merge. ... Conflicts: Text conflict in mysql-test/r/partition_innodb.result Text conflict in sql/field.h Text conflict in sql/item.h Text conflict in sql/item_cmpfunc.h Text conflict in sql/item_sum.h Text conflict in sql/log_event_old.cc Text conflict in sql/protocol.cc Text conflict in sql/sql_select.cc Text conflict in sql/sql_yacc.yy	2010-03-20 23:23:42 +03:00
Staale Smedseng	c7fad393fd	Bug #49829 Many "hides virtual function" warnings with ... SunStudio SunStudio compilers of late warn about methods that might hide methods in base classes due to the use of overloading combined with overriding. SunStudio also warns about variables defined in local socpe or method arguments that have the same name as a member attribute of the class. This patch renames methods that might hide base class methods, to make it easier both for humans and compilers to see what is actually called. It also renames variables in local scope. sql/field.cc: Local scope variable or method argument same as class attribute. sql/item_cmpfunc.cc: Local scope variable or method argument same as class attribute. sql/item_create.cc: Renaming base class create() to create_func(). sql/item_create.h: Renaming base class create() to create_func(). sql/protocol.cc: Local scope variable or method argument same as class attribute. sql/sql_profile.cc: Local scope variable or method argument same as class attribute. sql/sql_select.cc: Local scope variable or method argument same as class attribute. sql/sql_yacc.yy: Renaming base class create() to create_func(). storage/federated/ha_federated.cc: Local scope variable or method argument same as class attribute. storage/myisammrg/ha_myisammrg.cc: Local scope variable or method argument same as class attribute.	2010-03-14 17:01:45 +01:00
Konstantin Osipov	093106f552	WL#5000 FLUSH TABLES|TABLE table_list WITH READ LOCK. ... Extend and implement the grammar that allows to FLUSH WITH READ LOCK a list of tables, rather than all of them. Incompatible grammar change: Previously one could perform FLUSH TABLES, HOSTS, PRIVILEGES in a single statement. After this change, FLUSH TABLES must always be alone on the list. Judging by the test suite, however, the old extended syntax was never or very rarely used. The new statement requires RELOAD ACL global privilege and LOCK_TABLES_ACL | SELECT_ACL on individual tables. In other words, it's an atomic combination of LOCK TALBES <list> READ and FLUSH TABLES <list>, and requires respective privileges. For additional information about the semantics, please see WL#5000 and the comment for flush_tables_with_read_lock() function in sql_parse.cc mysql-test/r/flush.result: Update test results (WL#5000). mysql-test/t/flush.test: Add test coverage for WL#5000. sql/sql_yacc.yy: Allow FLUSH TABLES <table_list> WITH READ LOCK. Disallow FLUSH TABLES <table_list>, flush_options.	2010-02-27 20:05:14 +03:00