Push the patch of Jan Lindstrom: better comments
ha_innodb.cc:
Partial fix for Bug #12263 : we let InnoDB always to perform a rollback on the trx object if MySQL closes a connection; but we do print a warning to the .err log if an InnoDB transaction was active; we may remove that print later, since the situation really is not a bug; MySQL just is not aware that some cursor operation started an InnoDB transaction
cursors for InnoDB. The idea of the patch is that if MySQL requests
a consistent read view, we open one when open a cursor, set is as the
active view to a transaction when fetch from the cursor, and close
together with cursor close. This patch is associated to bugs #11813,
#11832, and #11833. Contains after review fixes.
Since UNLOCK TABLES will commit the transaction (and thus release
all InnoDB locks held by it), it is unnecessary to release the
user-requested table locks separately.
If MySQL wrote to its binlog, but for some reason trx->update_undo and trx->insert_undo were NULL in InnoDB, then trx->commit_lsn was garbage, and InnoDB could assert in the log flush of trx_commit_complete_for_mysql() (Bug #9277)
Add a settable session variable innodb_support_xa; setting it to 0 can save up to 10 % of CPU time and 150 bytes of space in each undo log
trx0trx.h, trx0undo.c, trx0trx.c, trx0roll.c:
Enable XA if innodb_support_xa is not set to 0; make prepare to do log fsync's according to innodb_flush_log_at_trx_commit
Fix InnoDB critical bug #7496; we scan the InnoDB data dictionary also at a normal mysqld startup, and create the spaces, so that we know the mapping space id -> .ibd file name; fix an infinite loop if DISCARD TABLESPACE coincides with INSERT or some other table operation; fix a potential crash if DISCARD TABLESPACE coincides with a cascaded FOREIGN KEY operation in the same table; do not allow DISCARD TABLESPACE of a referenced table if FOREIGN_KEY_CHECKS=1
transactional table locks to tables mentioned in the query. These locks
are released at the end of the transaction automatically.
This is fix for bugs #5655, #5998 and issue #3762.
locks all rows (BUG #3300). When using innobase_locks_unsafe_for_binlog
option InnoDB does not take locks for those rows which do not
belong to the result set or werent changed by the query. This fix removes
unnecessary locks also from SELECT and DELETE queries.
Reserve the MySQL LOCK_thread_count mutex when printing thd->query of
an arbitrary transaction; if we are printing thd->query of a transaction that
we know is currently executing inside InnoDB, then we know that MySQL cannot
meanwhile change thd->query, and no need to reserve the MySQL mutex; note
that this patch still leaves open the possibility of races in MySQL's
thd->query_len
Merge InnoDB-4.0.14: SAVEPOINT now implemented; InnoDB now accepts also column prefix keys; crashing bug in ON UPDATE CASCADE fixed; page checksum formula fixed
Remove code never actually used in IGNORE; InnoDB just rolls back the latest row insert or update on a duplicate key error and leaves it for MySQL to decide whether to ignore the error
Fix hang introduced by selective deadlock resolution
srv0srv.c, row0mysql.c:
Fix hang introduced by selective deadlock resolution + corruption caused by lock timeout or sel deadl res in ON DELETE CASCADE
Merge InnoDB-4.0.5: new isolation levels READ COMMITTED and READ UNCOMMITTED now supported, selective deadlock resolution
mysqld.cc:
Change MySQL default isolation level to REPEATABLE READ; note that InnoDB has always had that default, and BDB and MyISAM always run at SERIALIZABLE level anyway
