mariadb/mysql-test/t/not_embedded_server.test
Konstantin Osipov 0b39c189ba 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.
2009-12-05 02:02:48 +03:00

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#
# Here we collect tests that doesn't work with the embedded server
#
-- source include/not_embedded.inc
# The following fails sporadically because 'check-testcase' runs
# queries before this test and there is no way to guarantee that any
# previous process finishes. The purpose of the test is not clearly
# stated, there is no reference to any bug report, and "select from
# I_S from prepared statement" doesn't look like something that's
# really imporant to test. I'm commenting out this for now. If
# anyone wants to keep this, please fix the race and motivate why we
# need to test this. If you see this comment and it is after mid-2009
# or so, feel free to remove this test from the file. /Sven
#
#
## Show full process list with prepare
## To not show other connections, this must be the first test and we must
## have a server restart before this one
##
## We don't have any 4.1 tests as we use I_S to query the PROCESSLIST to
## exclude system threads that may/may not be active in the server
## (namely the ndb injector thread)
##
## End of 4.1 tests
#
#prepare stmt1 from ' SELECT * FROM INFORMATION_SCHEMA.PROCESSLIST WHERE COMMAND!=\'Daemon\' ';
#--replace_column 1 number 6 time 3 localhost
#execute stmt1;
#deallocate prepare stmt1;
call mtr.add_suppression("Can't open and lock privilege tables: Table 'host' was not locked with LOCK TABLES");
#
# Bug#43835: SHOW VARIABLES does not include 0 for slave_skip_errors
#
SHOW VARIABLES like 'slave_skip_errors';
# End of 5.1 tests
--echo #
--echo # WL#4284: Transactional DDL locking
--echo #
--echo # FLUSH PRIVILEGES should not implicitly unlock locked tables.
--echo #
--disable_warnings
drop table if exists t1;
--enable_warnings
create table t1 (c1 int);
lock tables t1 read;
--error ER_TABLE_NOT_LOCKED
flush privileges;
unlock tables;
drop table t1;