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Author SHA1 Message Date
Jon Olav Hauglid
5f352c2887 Bug #56448 Assertion failed: ! is_set() with second xa end
The problem was that issuing XA END when the XA transaction was
already ended, caused an assertion. This assertion tests that 
the server does not try to send OK to the client if there has
already been an error reported. The bug was only noticeable on
debug versions of the server.

The reason for the problem was that the trans_xa_end() function
reported success if the transaction was at XA_IDLE state at the
end regardless of any errors occured during processing of
trans_xa_end(). So if the transaction state was XA_IDLE already,
reported errors would be ignored.

This patch fixes the problem by having trans_xa_end() take into
consideration any reported errors. The patch also fixes a similar
bug with XA PREPARE.

Test case added to xa.test.
2010-09-13 13:31:22 +02:00
Konstantin Osipov
36290c0923 A pre-requisite patch for the fix for Bug#52044.
This patch also fixes Bug#55452 "SET PASSWORD is
replicated twice in RBR mode".

The goal of this patch is to remove the release of 
metadata locks from close_thread_tables().
This is necessary to not mistakenly release
the locks in the course of a multi-step
operation that involves multiple close_thread_tables()
or close_tables_for_reopen().

On the same token, move statement commit outside 
close_thread_tables().

Other cleanups:
Cleanup COM_FIELD_LIST.
Don't call close_thread_tables() in COM_SHUTDOWN -- there
are no open tables there that can be closed (we leave
the locked tables mode in THD destructor, and this
close_thread_tables() won't leave it anyway).

Make open_and_lock_tables() and open_and_lock_tables_derived()
call close_thread_tables() upon failure.
Remove the calls to close_thread_tables() that are now
unnecessary.

Simplify the back off condition in Open_table_context.

Streamline metadata lock handling in LOCK TABLES 
implementation.

Add asserts to ensure correct life cycle of 
statement transaction in a session.

Remove a piece of dead code that has also become redundant
after the fix for Bug 37521.

mysql-test/r/variables.result:
  Update results: set @@autocommit and statement transaction/
  prelocked mode.
mysql-test/r/view.result:
  A harmless change in CHECK TABLE <view> status for a broken view.
  If previously a failure to prelock all functions used in a view 
  would leave the connection in LTM_PRELOCKED mode, now we call
  close_thread_tables() from open_and_lock_tables()
  and leave prelocked mode, thus some check in mysql_admin_table() that
  works only in prelocked/locked tables mode is no longer activated.
mysql-test/suite/rpl/r/rpl_row_implicit_commit_binlog.result:
  Fixed Bug#55452 "SET PASSWORD is replicated twice in
  RBR mode": extra binlog events are gone from the
  binary log.
mysql-test/t/variables.test:
  Add a test case: set autocommit and statement transaction/prelocked
  mode.
sql/event_data_objects.cc:
  Simplify code in Event_job_data::execute().
  Move sp_head memory management to lex_end().
sql/event_db_repository.cc:
  Move the release of metadata locks outside
  close_thread_tables().
  Make sure we call close_thread_tables() when
  open_and_lock_tables() fails and remove extra
  code from the events data dictionary.
  Use close_mysql_tables(), a new internal
  function to properly close mysql.* tables
  in the data dictionary.
  Contract Event_db_repository::drop_events_by_field,
  drop_schema_events into one function.
  When dropping all events in a schema,
  make sure we don't mistakenly release all
  locks acquired by DROP DATABASE. These
  include locks on the database name
  and the global intention exclusive
  metadata lock.
sql/event_db_repository.h:
  Function open_event_table() does not require an instance 
  of Event_db_repository.
sql/events.cc:
  Use close_mysql_tables() instead of close_thread_tables()
  to bootstrap events, since the latter no longer
  releases metadata locks.
sql/ha_ndbcluster.cc:
  - mysql_rm_table_part2 no longer releases
  acquired metadata locks. Do it in the caller.
sql/ha_ndbcluster_binlog.cc:
  Deploy the new protocol for closing thread
  tables in run_query() and ndb_binlog_index
  code.
sql/handler.cc:
  Assert that we never call ha_commit_trans/
  ha_rollback_trans in sub-statement, which
  is now the case.
sql/handler.h:
  Add an accessor to check whether THD_TRANS object
  is empty (has no transaction started).
sql/log.cc:
  Update a comment.
sql/log_event.cc:
  Since now we commit/rollback statement transaction in 
  mysql_execute_command(), we need a mechanism to communicate
  from Query_log_event::do_apply_event() to mysql_execute_command()
  that the statement transaction should be rolled back, not committed.
  Ideally it would be a virtual method of THD. I hesitate
  to make THD a virtual base class in this already large patch.
  Use a thd->variables.option_bits for now.
  
  Remove a call to close_thread_tables() from the slave IO
  thread. It doesn't open any tables, and the protocol
  for closing thread tables is more complicated now.
  
  Make sure we properly close thread tables, however, 
  in Load_data_log_event, which doesn't
  follow the standard server execution procedure
  with mysql_execute_command().
  @todo: this piece should use Server_runnable
  framework instead.
  Remove an unnecessary call to mysql_unlock_tables().
sql/rpl_rli.cc:
  Update Relay_log_info::slave_close_thread_tables()
  to follow the new close protocol.
sql/set_var.cc:
  Remove an unused header.
sql/slave.cc:
  Remove an unnecessary call to
  close_thread_tables().
sql/sp.cc:
  Remove unnecessary calls to close_thread_tables()
  from SP DDL implementation. The tables will
  be closed by the caller, in mysql_execute_command().
  When dropping all routines in a database, make sure
  to not mistakenly drop all metadata locks acquired
  so far, they include the scoped lock on the schema.
sql/sp_head.cc:
  Correct the protocol that closes thread tables
  in an SP instruction.
  Clear lex->sphead before cleaning up lex
  with lex_end to make sure that we don't
  delete the sphead twice. It's considered
  to be "cleaner" and more in line with
  future changes than calling delete lex->sphead
  in other places that cleanup the lex.
sql/sp_head.h:
  When destroying m_lex_keeper of an instruction,
  don't delete the sphead that all lex objects
  share. 
  @todo: don't store a reference to routine's sp_head
  instance in instruction's lex.
sql/sql_acl.cc:
  Don't call close_thread_tables() where the caller will
  do that for us.
  Fix Bug#55452 "SET PASSWORD is replicated twice in RBR 
  mode" by disabling RBR replication in change_password()
  function.
  Use close_mysql_tables() in bootstrap and ACL reload
  code to make sure we release all metadata locks.
sql/sql_base.cc:
  This is the main part of the patch:
  - remove manipulation with thd->transaction
  and thd->mdl_context from close_thread_tables().
  Now this function is only responsible for closing
  tables, nothing else.
  This is necessary to be able to easily use
  close_thread_tables() in procedures, that
  involve multiple open/close tables, which all
  need to be protected continuously by metadata
  locks.
  Add asserts ensuring that TABLE object
  is only used when is protected by a metadata lock.
  Simplify the back off condition of Open_table_context,
  we no longer need to look at the autocommit mode.
  Make open_and_lock_tables() and open_normal_and_derived_tables()
  close thread tables and release metadata locks acquired so-far 
  upon failure. This simplifies their usage.
  Implement close_mysql_tables().
sql/sql_base.h:
  Add declaration for close_mysql_tables().
sql/sql_class.cc:
  Remove a piece of dead code that has also become redundant
  after the fix for Bug 37521.
  The code became dead when my_eof() was made a non-protocol method,
  but a method that merely modifies the diagnostics area.
  The code became redundant with the fix for Bug#37521, when 
  we started to cal close_thread_tables() before
  Protocol::end_statement().
sql/sql_do.cc:
  Do nothing in DO if inside a substatement
  (the assert moved out of trans_rollback_stmt).
sql/sql_handler.cc:
  Add comments.
sql/sql_insert.cc:
  Remove dead code. 
  Release metadata locks explicitly at the
  end of the delayed insert thread.
sql/sql_lex.cc:
  Add destruction of lex->sphead to lex_end(),
  lex "reset" method called at the end of each statement.
sql/sql_parse.cc:
  Move close_thread_tables() and other related
  cleanups to mysql_execute_command()
  from dispatch_command(). This has become
  possible after the fix for Bug#37521.
  Mark federated SERVER statements as DDL.
  
  Next step: make sure that we don't store
  eof packet in the query cache, and move
  the query cache code outside mysql_parse.
  
  Brush up the code of COM_FIELD_LIST.
  Remove unnecessary calls to close_thread_tables().
  
  When killing a query, don't report "OK"
  if it was a suicide.
sql/sql_parse.h:
  Remove declaration of a function that is now static.
sql/sql_partition.cc:
  Remove an unnecessary call to close_thread_tables().
sql/sql_plugin.cc:
  open_and_lock_tables() will clean up
  after itself after a failure.
  Move close_thread_tables() above
  end: label, and replace with close_mysql_tables(),
  which will also release the metadata lock
  on mysql.plugin.
sql/sql_prepare.cc:
  Now that we no longer release locks in close_thread_tables()
  statement prepare code has become more straightforward.
  Remove the now redundant check for thd->killed() (used
  only by the backup project) from Execute_server_runnable.
  Reorder code to take into account that now mysql_execute_command()
  performs lex->unit.cleanup() and close_thread_tables().
sql/sql_priv.h:
  Add a new option to server options to interact
  between the slave SQL thread and execution
  framework (hack). @todo: use a virtual
  method of class THD instead.
sql/sql_servers.cc:
  Due to Bug 25705 replication of 
  DROP/CREATE/ALTER SERVER is broken.
  Make sure at least we do not attempt to 
  replicate these statements using RBR,
  as this violates the assert in close_mysql_tables().
sql/sql_table.cc:
  Do not release metadata locks in mysql_rm_table_part2,
  this is done by the caller.
  Do not call close_thread_tables() in mysql_create_table(),
  this is done by the caller. 
  Fix a bug in DROP TABLE under LOCK TABLES when,
  upon error in wait_while_table_is_used() we would mistakenly
  release the metadata lock on a non-dropped table.
  Explicitly release metadata locks when doing an implicit
  commit.
sql/sql_trigger.cc:
  Now that we delete lex->sphead in lex_end(),
  zero the trigger's sphead in lex after loading
  the trigger, to avoid double deletion.
sql/sql_udf.cc:
  Use close_mysql_tables() instead of close_thread_tables().
sql/sys_vars.cc:
  Remove code added in scope of WL#4284 which would
  break when we perform set @@session.autocommit along
  with setting other variables and using tables or functions.
  A test case added to variables.test.
sql/transaction.cc:
  Add asserts.
sql/tztime.cc:
  Use close_mysql_tables() rather than close_thread_tables().
2010-07-27 14:25:53 +04:00
Jon Olav Hauglid
47edc4cade Bug #50124 Rpl failure on DROP table with concurrent txn/non-txn
DML flow and SAVEPOINT

The problem was that replication could break if a transaction involving
both transactional and non-transactional tables was rolled back to a
savepoint. It broke if a concurrent connection tried to drop a
transactional table which was locked after the savepoint was set.
This DROP TABLE completed when ROLLBACK TO SAVEPOINT was executed as the
lock on the table was dropped by the transaction. When the slave later
tried to apply the binlog, it would fail as the table would already
have been dropped.

The reason for the problem is that transactions involving both
transactional and non-transactional tables are written fully to the
binlog during ROLLBACK TO SAVEPOINT. At the same time, metadata locks
acquired after a savepoint, were released during ROLLBACK TO SAVEPOINT.
This allowed a second connection to drop a table only used between
SAVEPOINT and ROLLBACK TO SAVEPOINT. Which caused the transaction binlog
to refer to a non-existing table when it was written during ROLLBACK
TO SAVEPOINT.

This patch fixes the problem by not releasing metadata locks when
ROLLBACK TO SAVEPOINT is executed if binlogging is enabled.
2010-06-25 09:32:24 +02:00
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
Konstantin Osipov
9e62cf67b3 Clean-up, give better names, add comments to
thd->in_multi_stmt_transaction() and thd->active_transaction().


include/mysql_com.h:
  Comment SERVER_STATUS_IN_TRANS flag.
sql/ha_ndbcluster.cc:
  Rename: thd->in_multi_stmt_transaction() -> 
  thd->in_multi_stmt_transaction_mode().
sql/handler.cc:
  Add comments.
sql/log.cc:
  Rename: thd->in_multi_stmt_transaction() -> 
  thd->in_multi_stmt_transaction_mode().
sql/log_event.cc:
  Rename: thd->in_multi_stmt_transaction() -> 
  thd->in_multi_stmt_transaction_mode().
sql/sql_base.cc:
  Rename: thd->in_multi_stmt_transaction() -> 
  thd->in_multi_stmt_transaction_mode().
sql/sql_cache.cc:
  Rename: thd->active_transaction() ->
  thd->in_active_multi_stmt_transaction().
sql/sql_class.cc:
  Rename: thd->in_multi_stmt_transaction() -> 
  thd->in_multi_stmt_transaction_mode().
sql/sql_class.h:
  Rename and comment two transaction processing- related methods.
sql/sql_parse.cc:
  Rename: thd->in_multi_stmt_transaction() -> 
  thd->in_multi_stmt_transaction_mode().
  Rename: thd->active_transaction() ->
  thd->in_active_multi_stmt_transaction().
sql/sql_prepare.cc:
  Rename: thd->in_multi_stmt_transaction() -> 
  thd->in_multi_stmt_transaction_mode().
sql/sql_rename.cc:
  Rename: thd->active_transaction() ->
  thd->in_active_multi_stmt_transaction().
sql/sql_table.cc:
  Rename: thd->active_transaction() ->
  thd->in_active_multi_stmt_transaction().
sql/sys_vars.cc:
  Rename: thd->active_transaction() ->
  thd->in_active_multi_stmt_transaction().
sql/transaction.cc:
  Rename: thd->in_multi_stmt_transaction() -> 
  thd->in_multi_stmt_transaction_mode().
  Rename: thd->active_transaction() ->
  thd->in_active_multi_stmt_transaction().
2010-05-06 02:02:08 +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
Konstantin Osipov
056ac55aa0 Merge next-mr -> next-4284. 2010-02-03 03:06:42 +03:00
Dmitry Lenev
eba5d30e67 Implement new type-of-operation-aware metadata locks.
Add a wait-for graph based deadlock detector to the
MDL subsystem.

Fixes bug #46272 "MySQL 5.4.4, new MDL: unnecessary deadlock" and
bug #37346 "innodb does not detect deadlock between update and
alter table".

The first bug manifested itself as an unwarranted abort of a
transaction with ER_LOCK_DEADLOCK error by a concurrent ALTER
statement, when this transaction tried to repeat use of a
table, which it has already used in a similar fashion before
ALTER started.

The second bug showed up as a deadlock between table-level
locks and InnoDB row locks, which was "detected" only after
innodb_lock_wait_timeout timeout.

A transaction would start using the table and modify a few
rows.
Then ALTER TABLE would come in, and start copying rows
into a temporary table. Eventually it would stumble on
the modified records and get blocked on a row lock.
The first transaction would try to do more updates, and get
blocked on thr_lock.c lock.
This situation of circular wait would only get resolved
by a timeout.

Both these bugs stemmed from inadequate solutions to the
problem of deadlocks occurring between different
locking subsystems.

In the first case we tried to avoid deadlocks between metadata
locking and table-level locking subsystems, when upgrading shared
metadata lock to exclusive one.
Transactions holding the shared lock on the table and waiting for
some table-level lock used to be aborted too aggressively.

We also allowed ALTER TABLE to start in presence of transactions
that modify the subject table. ALTER TABLE acquires
TL_WRITE_ALLOW_READ lock at start, and that block all writes
against the table (naturally, we don't want any writes to be lost
when switching the old and the new table). TL_WRITE_ALLOW_READ
lock, in turn, would block the started transaction on thr_lock.c
lock, should they do more updates. This, again, lead to the need
to abort such transactions.

The second bug occurred simply because we didn't have any
mechanism to detect deadlocks between the table-level locks
in thr_lock.c and row-level locks in InnoDB, other than
innodb_lock_wait_timeout.

This patch solves both these problems by moving lock conflicts
which are causing these deadlocks into the metadata locking
subsystem, thus making it possible to avoid or detect such
deadlocks inside MDL.

To do this we introduce new type-of-operation-aware metadata
locks, which allow MDL subsystem to know not only the fact that
transaction has used or is going to use some object but also what
kind of operation it has carried out or going to carry out on the
object.

This, along with the addition of a special kind of upgradable
metadata lock, allows ALTER TABLE to wait until all
transactions which has updated the table to go away.
This solves the second issue.
Another special type of upgradable metadata lock is acquired
by LOCK TABLE WRITE. This second lock type allows to solve the
first issue, since abortion of table-level locks in event of
DDL under LOCK TABLES becomes also unnecessary.

Below follows the list of incompatible changes introduced by
this patch:

- From now on, ALTER TABLE and CREATE/DROP TRIGGER SQL (i.e. those
  statements that acquire TL_WRITE_ALLOW_READ lock)
  wait for all transactions which has *updated* the table to
  complete.

- From now on, LOCK TABLES ... WRITE, REPAIR/OPTIMIZE TABLE
  (i.e. all statements which acquire TL_WRITE table-level lock) wait
  for all transaction which *updated or read* from the table
  to complete.
  As a consequence, innodb_table_locks=0 option no longer applies
  to LOCK TABLES ... WRITE.

- DROP DATABASE, DROP TABLE, RENAME TABLE no longer abort
  statements or transactions which use tables being dropped or
  renamed, and instead wait for these transactions to complete.

- Since LOCK TABLES WRITE now takes a special metadata lock,
  not compatible with with reads or writes against the subject table
  and transaction-wide, thr_lock.c deadlock avoidance algorithm
  that used to ensure absence of deadlocks between LOCK TABLES
  WRITE and other statements is no longer sufficient, even for
  MyISAM. The wait-for graph based deadlock detector of MDL
  subsystem may sometimes be necessary and is involved. This may
  lead to ER_LOCK_DEADLOCK error produced for multi-statement
  transactions even if these only use MyISAM:

  session 1:         session 2:
  begin;

  update t1 ...      lock table t2 write, t1 write;
                     -- gets a lock on t2, blocks on t1

  update t2 ...
  (ER_LOCK_DEADLOCK)

- Finally,  support of LOW_PRIORITY option for LOCK TABLES ... WRITE
  was abandoned.
  LOCK TABLE ... LOW_PRIORITY WRITE from now on has the same
  priority as the usual LOCK TABLE ... WRITE.
  SELECT HIGH PRIORITY no longer trumps LOCK TABLE ... WRITE  in
  the wait queue.

- We do not take upgradable metadata locks on implicitly
  locked tables. So if one has, say, a view v1 that uses
  table t1, and issues:
  LOCK TABLE v1 WRITE;
  FLUSH TABLE t1; -- (or just 'FLUSH TABLES'),
  an error is produced.
  In order to be able to perform DDL on a table under LOCK TABLES,
  the table must be locked explicitly in the LOCK TABLES list.

mysql-test/include/handler.inc:
  Adjusted test case to trigger an execution path on which bug 41110
  "crash with handler command when used concurrently with alter
  table" and bug 41112 "crash in mysql_ha_close_table/get_lock_data
  with alter table" were originally discovered. Left old test case
  which no longer triggers this execution path for the sake of
  coverage.
  Added test coverage for HANDLER SQL statements and type-aware
  metadata locks.
  Added a test for the global shared lock and HANDLER SQL.
  Updated tests to take into account that the old simple deadlock
  detection heuristics was replaced with a graph-based deadlock
  detector.
mysql-test/r/debug_sync.result:
  Updated results (see debug_sync.test).
mysql-test/r/handler_innodb.result:
  Updated results (see handler.inc test).
mysql-test/r/handler_myisam.result:
  Updated results (see handler.inc test).
mysql-test/r/innodb-lock.result:
  Updated results (see innodb-lock.test).
mysql-test/r/innodb_mysql_lock.result:
  Updated results (see innodb_mysql_lock.test).
mysql-test/r/lock.result:
  Updated results (see lock.test).
mysql-test/r/lock_multi.result:
  Updated results (see lock_multi.test).
mysql-test/r/lock_sync.result:
  Updated results (see lock_sync.test).
mysql-test/r/mdl_sync.result:
  Updated results (see mdl_sync.test).
mysql-test/r/sp-threads.result:
  SHOW PROCESSLIST output has changed due to the fact that waiting
  for LOCK TABLES WRITE now happens within metadata locking
  subsystem.
mysql-test/r/truncate_coverage.result:
  Updated results (see truncate_coverage.test).
mysql-test/suite/funcs_1/datadict/processlist_val.inc:
  SELECT FROM I_S.PROCESSLIST output has changed due to fact that
  waiting for LOCK TABLES WRITE now happens within metadata locking
  subsystem.
mysql-test/suite/funcs_1/r/processlist_val_no_prot.result:
  SELECT FROM I_S.PROCESSLIST output has changed due to fact that
  waiting for LOCK TABLES WRITE now happens within metadata locking
  subsystem.
mysql-test/suite/rpl/t/rpl_sp.test:
  Updated to a new SHOW PROCESSLIST state name.
mysql-test/t/debug_sync.test:
  Use LOCK TABLES READ instead of LOCK TABLES WRITE as the latter
  no longer allows to trigger execution path involving waiting on
  thr_lock.c lock and therefore reaching debug sync-point covered
  by this test.
mysql-test/t/innodb-lock.test:
  Adjusted test case to the fact that innodb_table_locks=0 option is
  no longer supported, since LOCK TABLES WRITE handles all its
  conflicts within MDL subsystem.
mysql-test/t/innodb_mysql_lock.test:
  Added test for bug #37346 "innodb does not detect deadlock between
  update and alter table".
mysql-test/t/lock.test:
  Added test coverage which checks the fact that we no longer support
  DDL under LOCK TABLES on tables which were locked implicitly.
  Adjusted existing test cases accordingly.
mysql-test/t/lock_multi.test:
  Added test for bug #46272 "MySQL 5.4.4, new MDL: unnecessary
  deadlock".  Adjusted other test cases to take into account the
  fact that waiting for LOCK TABLES ... WRITE now happens within MDL
  subsystem.
mysql-test/t/lock_sync.test:
  Since LOCK TABLES ... WRITE now takes SNRW metadata lock for
  tables locked explicitly we have to implicitly lock InnoDB tables
  (through view) to trigger the table-level lock conflict between
  TL_WRITE and TL_WRITE_ALLOW_WRITE.
mysql-test/t/mdl_sync.test:
  Added basic test coverage for type-of-operation-aware metadata
  locks. Also covered with tests some use cases involving HANDLER
  statements in which a deadlock could arise.
  Adjusted existing tests to take type-of-operation-aware MDL into
  account.
mysql-test/t/multi_update.test:
  Update to a new SHOW PROCESSLIST state name.
mysql-test/t/truncate_coverage.test:
  Adjusted test case after making LOCK TABLES WRITE to wait until
  transactions that use the table to be locked are completed.
  Updated to the changed name of DEBUG_SYNC point.
sql/handler.cc:
  Global read lock functionality has been
  moved into a class.
sql/lock.cc:
  Global read lock functionality has been
  moved into a class.
  Updated code to use the new MDL API.
sql/mdl.cc:
  Introduced new type-of-operation aware metadata locks.
  To do this:
  - Changed MDL_lock to use one list for waiting requests and one
    list for granted requests. For each list, added a bitmap
    that holds information what lock types a list contains.
    Added a helper class MDL_lock::List to manipulate with granted
    and waited lists while keeping the bitmaps in sync
    with list contents.
  - Changed lock-compatibility functions to use bitmaps that
    define compatibility.
  - Introduced a graph based deadlock detector inspired by
    waiting_threads.c from Maria implementation.
  - Now that we have a deadlock detector, and no longer have
    a global lock to protect individual lock objects, but rather
    use an rw lock per object, removed redundant code for upgrade,
    and the global read lock. Changed the MDL API to
    no longer require the caller to acquire the global
    intention exclusive lock by means of a separate method.
    Removed a few more methods that became redundant.
  - Removed deadlock detection heuristic, it has been made
    obsolete by the deadlock detector.
  - With operation-type-aware metadata locks, MDL subsystem has
    become aware of potential conflicts between DDL and open
    transactions. This made it possible to remove calls to
    mysql_abort_transactions_with_shared_lock() from acquisition
    paths for exclusive lock and lock upgrade. Now we can simply
    wait for these transactions to complete without fear of
    deadlock. Function mysql_lock_abort() has also become
    unnecessary for all conflicting cases except when a DDL
    conflicts with a connection that has an open HANDLER.
sql/mdl.h:
  Introduced new type-of-operation aware metadata locks.
  Introduced a graph based deadlock detector and supporting
  methods.
  Added comments.
  God rid of redundant API calls.
  Renamed m_lt_or_ha_sentinel to m_trans_sentinel,
  since now it guards the global read lock as well as
  LOCK TABLES and HANDLER locks.
sql/mysql_priv.h:
  Moved the global read lock functionality into a
  class.
  Added MYSQL_OPEN_FORCE_SHARED_MDL flag which forces
  open_tables() to take MDL_SHARED on tables instead of
  metadata locks specified in the parser. We use this to
  allow PREPARE run concurrently in presence of
  LOCK TABLES ... WRITE.
  Added signature for find_table_for_mdl_ugprade().
sql/set_var.cc:
  Global read lock functionality has been
  moved into a class.
sql/sp_head.cc:
  When creating TABLE_LIST elements for prelocking or
  system tables set the type of request for metadata
  lock according to the operation that will be performed
  on the table.
sql/sql_base.cc:
  - Updated code to use the new MDL API.
  - In order to avoid locks starvation we take upgradable
    locks all at once. As result implicitly locked tables no
    longer get an upgradable lock. Consequently DDL and FLUSH
    TABLES for such tables is prohibited.
    find_write_locked_table() was replaced by
    find_table_for_mdl_upgrade() function.
    open_table() was adjusted to return TABLE instance with
    upgradable ticket when necessary.
  - We no longer wait for all locks on OT_WAIT back off
    action -- only on the lock that caused the wait
    conflict. Moreover, now we distinguish cases when we
    have to wait due to conflict in MDL and old version
    of table in TDC.
  - Upate mysql_notify_threads_having_share_locks()
    to only abort thr_lock.c waits of threads that
    have open HANDLERs, since lock conflicts with only
    these threads now can lead to deadlocks not detectable
    by the MDL deadlock detector.
  - Remove mysql_abort_transactions_with_shared_locks()
    which is no longer needed.
sql/sql_class.cc:
  Global read lock functionality has been moved into a class.
  Re-arranged code in THD::cleanup() to simplify assert.
sql/sql_class.h:
  Introduced class to incapsulate global read lock
  functionality.
  Now sentinel in MDL subsystem guards the global read lock
  as well as LOCK TABLES and HANDLER locks. Adjusted code
  accordingly.
sql/sql_db.cc:
  Global read lock functionality has been moved into a class.
sql/sql_delete.cc:
  We no longer acquire upgradable metadata locks on tables
  which are locked by LOCK TABLES implicitly. As result
  TRUNCATE TABLE is no longer allowed for such tables.
  Updated code to use the new MDL API.
sql/sql_handler.cc:
  Inform MDL_context about presence of open HANDLERs.
  Since HANLDERs break MDL protocol by acquiring table-level
  lock while holding only S metadata lock on a table MDL
  subsystem should take special care about such contexts (Now
  this is the only case when mysql_lock_abort() is used).
sql/sql_parse.cc:
  Global read lock functionality has been moved into a class.
  Do not take upgradable metadata locks when opening tables
  for CREATE TABLE SELECT as it is not necessary and limits
  concurrency.
  When initializing TABLE_LIST objects before adding them
  to the table list set the type of request for metadata lock
  according to the operation that will be performed on the
  table.
  We no longer acquire upgradable metadata locks on tables
  which are locked by LOCK TABLES implicitly. As result FLUSH
  TABLES is no longer allowed for such tables.
sql/sql_prepare.cc:
  Use MYSQL_OPEN_FORCE_SHARED_MDL flag when opening
  tables during PREPARE. This allows PREPARE to run
  concurrently in presence of LOCK TABLES ... WRITE.
sql/sql_rename.cc:
  Global read lock functionality has been moved into a class.
sql/sql_show.cc:
  Updated code to use the new MDL API.
sql/sql_table.cc:
  Global read lock functionality has been moved into a class.
  We no longer acquire upgradable metadata locks on tables
  which are locked by LOCK TABLES implicitly. As result DROP
  TABLE is no longer allowed for such tables.
  Updated code to use the new MDL API.
sql/sql_trigger.cc:
  Global read lock functionality has been moved into a class.
  We no longer acquire upgradable metadata locks on tables
  which are locked by LOCK TABLES implicitly. As result
  CREATE/DROP TRIGGER is no longer allowed for such tables.
  Updated code to use the new MDL API.
sql/sql_view.cc:
  Global read lock functionality has been moved into a class.
  Fixed results of wrong merge that led to misuse of GLR API.
  CREATE VIEW statement is not a commit statement.
sql/table.cc:
  When resetting TABLE_LIST objects for PS or SP re-execution
  set the type of request for metadata lock according to the
  operation that will be performed on the table. Do the same
  in auxiliary function initializing metadata lock requests
  in a table list.
sql/table.h:
  When initializing TABLE_LIST objects set the type of request
  for metadata lock according to the operation that will be
  performed on the table.
sql/transaction.cc:
  Global read lock functionality has been moved into a class.
2010-02-01 14:43:06 +03:00
Konstantin Osipov
dfdbc84585 A prerequisite patch for the fix for Bug#46224
"HANDLER statements within a transaction might lead to deadlocks".
Introduce a notion of a sentinel to MDL_context. A sentinel
is a ticket that separates all tickets in the context into two
groups: before and after it. Currently we can have (and need) only
one designated sentinel -- it separates all locks taken by LOCK
TABLE or HANDLER statement, which must survive COMMIT and ROLLBACK
and all other locks, which must be released at COMMIT or ROLLBACK.
The tricky part is maintaining the sentinel up to date when
someone release its corresponding ticket. This can happen, e.g.
if someone issues DROP TABLE under LOCK TABLES (generally,
see all calls to release_all_locks_for_name()).
MDL_context::release_ticket() is modified to take care of it.

******
A fix and a test case for Bug#46224 "HANDLER statements within a
transaction might lead to deadlocks".

An attempt to mix HANDLER SQL statements, which are transaction-
agnostic, an open multi-statement transaction,
and DDL against the involved tables (in a concurrent connection) 
could lead to a deadlock. The deadlock would occur when
HANDLER OPEN or HANDLER READ would have to wait on a conflicting
metadata lock. If the connection that issued HANDLER statement
also had other metadata locks (say, acquired in scope of a 
transaction), a classical deadlock situation of mutual wait
could occur.

Incompatible change: entering LOCK TABLES mode automatically
closes all open HANDLERs in the current connection.

Incompatible change: previously an attempt to wait on a lock
in a connection that has an open HANDLER statement could wait
indefinitely/deadlock. After this patch, an error ER_LOCK_DEADLOCK
is produced.

The idea of the fix is to merge thd->handler_mdl_context
with the main mdl_context of the connection, used for transactional
locks. This makes deadlock detection possible, since all waits
with locks are "visible" and available to analysis in a single
MDL context of the connection.

Since HANDLER locks and transactional locks have a different life
cycle -- HANDLERs are explicitly open and closed, and so
are HANDLER locks, explicitly acquired and released, whereas
transactional locks "accumulate" till the end of a transaction
and are released only with COMMIT, ROLLBACK and ROLLBACK TO SAVEPOINT,
a concept of "sentinel" was introduced to MDL_context.
All locks, HANDLER and others, reside in the same linked list.
However, a selected element of the list separates locks with
different life cycle. HANDLER locks always reside at the
end of the list, after the sentinel. Transactional locks are
prepended to the beginning of the list, before the sentinel.
Thus, ROLLBACK, COMMIT or ROLLBACK TO SAVEPOINT, only
release those locks that reside before the sentinel. HANDLER locks
must be released explicitly as part of HANDLER CLOSE statement,
or an implicit close. 
The same approach with sentinel
is also employed for LOCK TABLES locks. Since HANDLER and LOCK TABLES
statement has never worked together, the implementation is
made simple and only maintains one sentinel, which is used either
for HANDLER locks, or for LOCK TABLES locks.


mysql-test/include/handler.inc:
  Add test coverage for Bug#46224 "HANDLER statements within a
  transaction might lead to deadlocks".
  Extended HANDLER coverage to cover a mix of HANDLER, transactions
  and DDL statements.
mysql-test/r/handler_innodb.result:
  Update results (Bug#46224).
mysql-test/r/handler_myisam.result:
  Update results (Bug#46224).
sql/lock.cc:
  Remove thd->some_tables_deleted, it's never used.
sql/log_event.cc:
  No need to check for thd->locked_tables_mode, 
  it's done inside release_transactional_locks().
sql/mdl.cc:
  Implement the concept of HANDLER and LOCK TABLES "sentinel".
  Implement a method to clone an acquired ticket.
  Do not return tickets beyond the sentinel when acquiring
  locks, create a copy.
  Remove methods to merge and backup MDL_context, they are now
  not used (Hurra!). This opens a path to a proper constructor
  and destructor of class MDL_context (to be done in a separate
  patch).
  Modify find_ticket() to provide information about where
  the ticket position is with regard to the sentinel.
sql/mdl.h:
  Add declarations necessary for the implementation of the concept
  of "sentinel", a dedicated ticket separating transactional and
  non-transactional locks.
sql/mysql_priv.h:
  Add mark_tmp_table_for_reuse() declaration, 
  a function to "close" a single session (temporary) table.
sql/sql_base.cc:
  Remove thd->some_tables_deleted.
  Modify deadlock-prevention asserts and deadlock detection
  heuristics to take into account that from now on HANDLER locks
  reside in the same locking context.
  Add broadcast_refresh() to mysql_notify_thread_having_shared_lock():
  this is necessary for the case when a thread having a shared lock
  is asleep in tdc_wait_for_old_versions(). This situation is only
  possible with HANDLER t1 OPEN; FLUSH TABLE (since all over code paths
  that lead to tdc_wait_for_old_versions() always have an
  empty MDL_context). Previously the server would simply deadlock
  in this situation.
sql/sql_class.cc:
  Remove now unused member "THD::some_tables_deleted". 
  Move mysql_ha_cleanup() a few lines above in THD::cleanup() 
  to make sure that all handlers are closed when it's time to 
  destroy the MDL_context of this connection.
  Remove handler_mdl_context and handler_tables.
sql/sql_class.h:
  Remove THD::handler_tables, THD::handler_mdl_context,
  THD::some_tables_deleted.
sql/sql_handler.cc:
  Remove thd->handler_tables.
  Remove thd->handler_mdl_context.
  Rewrite mysql_ha_open() to have no special provision for MERGE
  tables, now that we don't have to manipulate with thd->handler_tables
  it's easy to do.
  Remove dead code.
  Fix a bug in mysql_ha_flush() when we would always flush
  a temporary HANDLER when mysql_ha_flush() is called (actually
  mysql_ha_flush() never needs to flush temporary tables).
sql/sql_insert.cc:
  Update a comment, no more thd->some_tables_deleted.
sql/sql_parse.cc:
  Implement an incompatible change: entering LOCK TABLES closes
  active HANDLERs, if any.
  Now that we have a sentinel, we don't need to check
  for thd->locked_tables_mode when releasing metadata locks in
  COMMIT/ROLLBACK.
sql/sql_plist.h:
  Add new (now necessary) methods to the list class.
sql/sql_prepare.cc:
  Make sure we don't release HANDLER locks when rollback to a
  savepoint, set to not keep locks taken at PREPARE.
sql/sql_servers.cc:
  Update to a new signature of MDL_context::release_all_locks().
sql/sql_table.cc:
  Remove thd->some_tables_deleted.
sql/transaction.cc:
  Add comments. 
  Make sure rollback to (MDL) savepoint works under LOCK TABLES and
  with HANDLER tables.
2009-12-22 19:09:15 +03:00
Konstantin Osipov
a14bbee5ab Backport of revno ## 2617.31.1, 2617.31.3, 2617.31.4, 2617.31.5,
2617.31.12, 2617.31.15, 2617.31.15, 2617.31.16, 2617.43.1
- initial changeset that introduced the fix for 
Bug#989 and follow up fixes for all test suite failures
introduced in the initial changeset. 
------------------------------------------------------------
revno: 2617.31.1
committer: Davi Arnaut <Davi.Arnaut@Sun.COM>
branch nick: 4284-6.0
timestamp: Fri 2009-03-06 19:17:00 -0300
message:
Bug#989: If DROP TABLE while there's an active transaction, wrong binlog order
WL#4284: Transactional DDL locking

Currently the MySQL server does not keep metadata locks on
schema objects for the duration of a transaction, thus failing
to guarantee the integrity of the schema objects being used
during the transaction and to protect then from concurrent
DDL operations. This also poses a problem for replication as
a DDL operation might be replicated even thought there are
active transactions using the object being modified.

The solution is to defer the release of metadata locks until
a active transaction is either committed or rolled back. This
prevents other statements from modifying the table for the
entire duration of the transaction. This provides commitment
ordering for guaranteeing serializability across multiple
transactions.

- Incompatible change:

If MySQL's metadata locking system encounters a lock conflict,
the usual schema is to use the try and back-off technique to
avoid deadlocks -- this schema consists in releasing all locks
and trying to acquire them all in one go.

But in a transactional context this algorithm can't be utilized
as its not possible to release locks acquired during the course
of the transaction without breaking the transaction commitments.
To avoid deadlocks in this case, the ER_LOCK_DEADLOCK will be
returned if a lock conflict is encountered during a transaction.

Let's consider an example:

A transaction has two statements that modify table t1, then table
t2, and then commits. The first statement of the transaction will
acquire a shared metadata lock on table t1, and it will be kept
utill COMMIT to ensure serializability.

At the moment when the second statement attempts to acquire a
shared metadata lock on t2, a concurrent ALTER or DROP statement
might have locked t2 exclusively. The prescription of the current
locking protocol is that the acquirer of the shared lock backs off
-- gives up all his current locks and retries. This implies that
the entire multi-statement transaction has to be rolled back.

- Incompatible change:

FLUSH commands such as FLUSH PRIVILEGES and FLUSH TABLES WITH READ
LOCK won't cause locked tables to be implicitly unlocked anymore.


mysql-test/extra/binlog_tests/drop_table.test:
  Add test case for Bug#989.
mysql-test/extra/binlog_tests/mix_innodb_myisam_binlog.test:
  Fix test case to reflect the fact that transactions now hold
  metadata locks for the duration of a transaction.
mysql-test/include/mix1.inc:
  Fix test case to reflect the fact that transactions now hold
  metadata locks for the duration of a transaction.
mysql-test/include/mix2.inc:
  Fix test case to reflect the fact that transactions now hold
  metadata locks for the duration of a transaction.
mysql-test/r/flush_block_commit.result:
  Update test case result (WL#4284).
mysql-test/r/flush_block_commit_notembedded.result:
  Update test case result (WL#4284).
mysql-test/r/innodb.result:
  Update test case result (WL#4284).
mysql-test/r/innodb_mysql.result:
  Update test case result (WL#4284).
mysql-test/r/lock.result:
  Add test case result for an effect of WL#4284/Bug#989
  (all locks should be released when a connection terminates).
mysql-test/r/mix2_myisam.result:
  Update test case result (effects of WL#4284/Bug#989).
mysql-test/r/not_embedded_server.result:
  Update test case result (effects of WL#4284/Bug#989).
  Add a test case for interaction of WL#4284 and FLUSH PRIVILEGES.
mysql-test/r/partition_innodb_semi_consistent.result:
  Update test case result (effects of WL#4284/Bug#989).
mysql-test/r/partition_sync.result:
  Temporarily disable the test case for Bug#43867,
  which will be fixed by a subsequent backport.
mysql-test/r/ps.result:
  Add a test case for effect of PREPARE on transactional
  locks: we take a savepoint at beginning of PREAPRE
  and release it at the end. Thus PREPARE does not 
  accumulate metadata locks (Bug#989/WL#4284).
mysql-test/r/read_only_innodb.result:
  Update test case result (effects of WL#4284/Bug#989).
mysql-test/suite/binlog/r/binlog_row_drop_tbl.result:
  Add a test case result (WL#4284/Bug#989).
mysql-test/suite/binlog/r/binlog_row_mix_innodb_myisam.result:
  Update test case result (effects of WL#4284/Bug#989).
mysql-test/suite/binlog/r/binlog_stm_drop_tbl.result:
  Add a test case result (WL#4284/Bug#989).
mysql-test/suite/binlog/r/binlog_stm_mix_innodb_myisam.result:
  Update test case result (effects of WL#4284/Bug#989).
mysql-test/suite/binlog/r/binlog_unsafe.result:
  A side effect of Bug#989 -- slightly different table map ids.
mysql-test/suite/binlog/t/binlog_row_drop_tbl.test:
  Add a test case for WL#4284/Bug#989.
mysql-test/suite/binlog/t/binlog_stm_drop_tbl.test:
  Add a test case for WL#4284/Bug#989.
mysql-test/suite/binlog/t/binlog_stm_row.test:
  Update to the new state name. This
  is actually a follow up to another patch for WL#4284, 
  that changes Locked thread state to Table lock.
mysql-test/suite/ndb/r/ndb_index_ordered.result:
  Remove result for disabled part of the test case.
mysql-test/suite/ndb/t/disabled.def:
  Temporarily disable a test case (Bug#45621).
mysql-test/suite/ndb/t/ndb_index_ordered.test:
  Disable a part of a test case (needs update to
  reflect semantics of Bug#989).
mysql-test/suite/rpl/t/disabled.def:
  Disable tests made meaningless by transactional metadata
  locking.
mysql-test/suite/sys_vars/r/autocommit_func.result:
  Add a commit (Bug#989).
mysql-test/suite/sys_vars/t/autocommit_func.test:
  Add a commit (Bug#989).
mysql-test/t/flush_block_commit.test:
  Fix test case to reflect the fact that transactions now hold
  metadata locks for the duration of a transaction.
mysql-test/t/flush_block_commit_notembedded.test:
  Fix test case to reflect the fact that transactions now hold
  metadata locks for the duration of a transaction.
  Add a test case for transaction-scope locks and the global
  read lock (Bug#989/WL#4284).
mysql-test/t/innodb.test:
  Fix test case to reflect the fact that transactions now hold
  metadata locks for the duration of a transaction
  (effects of Bug#989/WL#4284).
mysql-test/t/lock.test:
  Add a test case for Bug#989/WL#4284.
mysql-test/t/not_embedded_server.test:
  Add a test case for Bug#989/WL#4284.
mysql-test/t/partition_innodb_semi_consistent.test:
  Replace TRUNCATE with DELETE, to not issue
  an implicit commit of a transaction, and not depend
  on metadata locks.
mysql-test/t/partition_sync.test:
  Temporarily disable the test case for Bug#43867,
  which needs a fix to be backported from 6.0.
mysql-test/t/ps.test:
  Add a test case for semantics of PREPARE and transaction-scope
  locks: metadata locks on tables used in PREPARE are enclosed into a
  temporary savepoint, taken at the beginning of PREPARE,
  and released at the end. Thus PREPARE does not effect
  what locks a transaction owns.
mysql-test/t/read_only_innodb.test:
  Fix test case to reflect the fact that transactions now hold
  metadata locks for the duration of a transaction 
  (Bug#989/WL#4284).
  
  Wait for the read_only statement to actually flush tables before
  sending other concurrent statements that depend on its state.
mysql-test/t/xa.test:
  Fix test case to reflect the fact that transactions now hold
  metadata locks for the duration of a transaction 
  (Bug#989/WL#4284).
sql/ha_ndbcluster_binlog.cc:
  Backport bits of changes of ha_ndbcluster_binlog.cc
  from 6.0, to fix the failing binlog test suite with
  WL#4284. WL#4284 implementation does not work
  with 5.1 implementation of ndbcluster binlog index.
sql/log_event.cc:
  Release metadata locks after issuing a commit.
sql/mdl.cc:
  Style changes (WL#4284).
sql/mysql_priv.h:
  Rename parameter to match the name used in the definition (WL#4284).
sql/rpl_injector.cc:
  Release metadata locks on commit (WL#4284).
sql/rpl_rli.cc:
  Remove assert made meaningless, metadata locks are released
  at the end of the transaction.
sql/set_var.cc:
  Close tables and release locks if autocommit mode is set.
sql/slave.cc:
  Release metadata locks after a rollback.
sql/sql_acl.cc:
  Don't implicitly unlock locked tables. Issue a implicit commit
  at the end and unlock tables.
sql/sql_base.cc:
  Defer the release of metadata locks when closing tables
  if not required to.
  Issue a deadlock error if the locking protocol requires
  that a transaction re-acquire its locks.
  
  Release metadata locks when closing tables for reopen.
sql/sql_class.cc:
  Release metadata locks if the thread is killed.
sql/sql_parse.cc:
  Release metadata locks after implicitly committing a active
  transaction, or after explicit commits or rollbacks.
sql/sql_plugin.cc:
  
  Allocate MDL request on the stack as the use of the table
  is contained within the function. It will be removed from
  the context once close_thread_tables is called at the end
  of the function.
sql/sql_prepare.cc:
  The problem is that the prepare phase of the CREATE TABLE
  statement takes a exclusive metadata lock lock and this can
  cause a self-deadlock the thread already holds a shared lock
  on the table being that should be created.
  
  The solution is to make the prepare phase take a shared
  metadata lock when preparing a CREATE TABLE statement. The
  execution of the statement will still acquire a exclusive
  lock, but won't cause any problem as it issues a implicit
  commit.
  
  After some discussions with stakeholders it has been decided that
  metadata locks acquired during a PREPARE statement must be released
  once the statement is prepared even if it is prepared within a multi
  statement transaction.
sql/sql_servers.cc:
  Don't implicitly unlock locked tables. Issue a implicit commit
  at the end and unlock tables.
sql/sql_table.cc:
  Close table and release metadata locks after a admin operation.
sql/table.h:
  The problem is that the prepare phase of the CREATE TABLE
  statement takes a exclusive metadata lock lock and this can
  cause a self-deadlock the thread already holds a shared lock
  on the table being that should be created.
  
  The solution is to make the prepare phase take a shared
  metadata lock when preparing a CREATE TABLE statement. The
  execution of the statement will still acquire a exclusive
  lock, but won't cause any problem as it issues a implicit
  commit.
sql/transaction.cc:
  Release metadata locks after the implicitly committed due
  to a new transaction being started. Also, release metadata
  locks acquired after a savepoint if the transaction is rolled
  back to the save point.
  
  The problem is that in some cases transaction-long metadata locks
  could be released before the transaction was committed. This could
  happen when a active transaction was ended by a "START TRANSACTION"
  or "BEGIN" statement, in which case the metadata locks would be
  released before the actual commit of the active transaction.
  
  The solution is to defer the release of metadata locks to after the
  transaction has been implicitly committed. No test case is provided
  as the effort to provide one is too disproportional to the size of
  the fix.
2009-12-05 02:02:48 +03:00
Konstantin Osipov
411a81954e ------------------------------------------------------------
revno: 2617.22.4
committer: Davi Arnaut <Davi.Arnaut@Sun.COM>
branch nick: mysql-6.0-runtime
timestamp: Mon 2009-01-26 15:19:14 -0200
message:
Move checks for OPTION_NOT_AUTOCOMMIT | OPTION_BEGIN to a separate
helper function.


sql/ha_ndbcluster.cc:
  Use helper method to check transaction mode.
sql/log.cc:
  Use helper method to check transaction mode.
sql/sql_cache.cc:
  Use helper method to check transaction mode.
sql/sql_class.cc:
  Use helper method to check transaction mode.
sql/sql_class.h:
  Add helper method to check whether session is in a multi-statement
  transaction.
sql/sql_parse.cc:
  Use helper method to check transaction mode.
sql/transaction.cc:
  Use helper method to check transaction mode.
2009-12-04 01:46:14 +03:00
Konstantin Osipov
c52d4830bf Backport of:
------------------------------------------------------------
revno: 2630.22.3
committer: Davi Arnaut <Davi.Arnaut@Sun.COM>
branch nick: 4284-6.0
timestamp: Thu 2008-08-07 22:33:43 -0300
message:
WL#4284: Transactional DDL locking

Make transaction management more modular through a new interface.

The overall objective of this change is to provide groundwork
for the design of transactional DDL locking by cleaning up the
transaction high level API to better distinguish operations implicit
and explicit, and single statement transaction from operations on
the normal transaction.

Having a a high-level interface for transaction management provides
a better base for implementing transactional concepts that are not
always tied to storage engines and also makes it easier to interect
with other higher level modules of the server.

client/Makefile.am:
  Add new file to the build.
libmysqld/CMakeLists.txt:
  Add new file to the build.
libmysqld/Makefile.am:
  Add new file to the build.
sql/CMakeLists.txt:
  Add new file to the build.
sql/Makefile.am:
  Add new file to the build.
sql/handler.cc:
  Remove multiplexer commit or rollback function. Most callers already
  have enough information to decided whether to rollback or commit.
  Having plain and well named functions makes it easier to read
  and understand code.
sql/handler.h:
  Remove wrapper function as the low level transaction functions
  shouldn't be called directly anymore.
sql/log_event.cc:
  Rename transaction management functions to the new names.
sql/log_event_old.cc:
  Rename transaction management functions to the new names.
sql/mysql_priv.h:
  Remove obsolete functions for implicit and explicit commit.
sql/rpl_injector.cc:
  Rename transaction management functions to the new names.
sql/rpl_rli.cc:
  Rename transaction management functions to the new names.
sql/set_var.cc:
  Rename transaction management functions to the new names.
sql/slave.cc:
  Rename transaction management functions to the new names.
sql/sql_base.cc:
  Rename transaction management functions to the new names.
sql/sql_class.cc:
  Rename transaction management functions to the new names.
sql/sql_delete.cc:
  Rename transaction management functions to the new names.
sql/sql_do.cc:
  Rename transaction management functions to the new names.
sql/sql_insert.cc:
  Rename transaction management functions to the new names.
sql/sql_parse.cc:
  Rename transaction management functions to the new names.
sql/sql_partition.cc:
  Rename transaction management functions to the new names.
sql/sql_table.cc:
  Rename transaction management functions to the new names.
sql/transaction.cc:
  Implement wrapper functions to differentiate operations on
  the single statement transaction from the ones operating
  on the normal transaction.
sql/transaction.h:
  Export new functions for dealing with transaction commands.
2009-12-03 21:37:38 +03:00