mariadb/mysql-test/r/schema.result

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drop database if exists mysqltest1;
create schema foo;
show create schema foo;
Database Create Database
foo CREATE DATABASE `foo` /*!40100 DEFAULT CHARACTER SET latin1 */
show schemas;
Database
information_schema
foo
2008-04-02 10:06:36 +02:00
mtr
mysql
performance_schema
test
drop schema foo;
Bug #48940 MDL deadlocks against mysql_rm_db This deadlock would occur between two connections A and B if statements where executed in the following way: 1) Connection A executes a DML statement against table s1.t1 with autocommit off. This causes a shared metadata lock on s1.t1 to be acquired. (With autocommit on, the metadata lock will be dropped once the statment completes and the deadlock will not occour.) 2) Connection B tries to DROP DATABASE s1. This will block against the metadata lock connection A holds on s1.t1. While blocking, connection B will hold the LOCK_mysql_create_db mutex. 3) Connection A tries to ALTER DATABASE s1. This will block when trying to get LOCK_mysql_create_db mutex held by connection B. 4) Deadlock between DROP DATABASE and ALTER DATABASE (which has autocommit off). If Connection A used an explicitly started transaction rather than having autocommit off, this deadlock did not happen as ALTER DATABASE is disallowed inside transactions. This patch fixes the problem by changing ALTER DATABASE to cause an implicit commit before executing. This will cause the metadata lock on s1.t1 to be dropped, allowing DROP DATABASE to proceed. This will in turn cause the LOCK_mysql_create_db mutex to be unlocked, allowing ALTER DATABASE to proceed. Note that SQL commands other than ALTER DATABASE that also use LOCK_mysql_create_db, already cause an implicit commit. Incompatible change: ALTER DATABASE (and its synonym ALTER SCHEMA) now cause an implicit commit. This must be reflected in the documentation. Test case added to schema.test.
2009-12-15 14:18:10 +01:00
#
# Bug #48940 MDL deadlocks against mysql_rm_db
#
DROP SCHEMA IF EXISTS schema1;
# Connection default
CREATE SCHEMA schema1;
CREATE TABLE schema1.t1 (a INT);
SET autocommit= FALSE;
INSERT INTO schema1.t1 VALUES (1);
# Connection 2
DROP SCHEMA schema1;
# Connection default
ALTER SCHEMA schema1 DEFAULT CHARACTER SET utf8;
2010-01-12 16:15:21 +01:00
Got one of the listed errors
Bug #48940 MDL deadlocks against mysql_rm_db This deadlock would occur between two connections A and B if statements where executed in the following way: 1) Connection A executes a DML statement against table s1.t1 with autocommit off. This causes a shared metadata lock on s1.t1 to be acquired. (With autocommit on, the metadata lock will be dropped once the statment completes and the deadlock will not occour.) 2) Connection B tries to DROP DATABASE s1. This will block against the metadata lock connection A holds on s1.t1. While blocking, connection B will hold the LOCK_mysql_create_db mutex. 3) Connection A tries to ALTER DATABASE s1. This will block when trying to get LOCK_mysql_create_db mutex held by connection B. 4) Deadlock between DROP DATABASE and ALTER DATABASE (which has autocommit off). If Connection A used an explicitly started transaction rather than having autocommit off, this deadlock did not happen as ALTER DATABASE is disallowed inside transactions. This patch fixes the problem by changing ALTER DATABASE to cause an implicit commit before executing. This will cause the metadata lock on s1.t1 to be dropped, allowing DROP DATABASE to proceed. This will in turn cause the LOCK_mysql_create_db mutex to be unlocked, allowing ALTER DATABASE to proceed. Note that SQL commands other than ALTER DATABASE that also use LOCK_mysql_create_db, already cause an implicit commit. Incompatible change: ALTER DATABASE (and its synonym ALTER SCHEMA) now cause an implicit commit. This must be reflected in the documentation. Test case added to schema.test.
2009-12-15 14:18:10 +01:00
SET autocommit= TRUE;
# Connection 2
# Connection default
2010-01-12 16:15:21 +01:00
#
# Bug #49988 MDL deadlocks with mysql_create_db, reload_acl_and_cache
#
DROP SCHEMA IF EXISTS schema1;
# Connection default
CREATE SCHEMA schema1;
CREATE TABLE schema1.t1 (id INT);
LOCK TABLE schema1.t1 WRITE;
# Connection con2
DROP SCHEMA schema1;
# Connection default
# CREATE SCHEMA used to give a deadlock.
# Now we prohibit CREATE SCHEMA in LOCK TABLES mode.
CREATE SCHEMA IF NOT EXISTS schema1;
ERROR HY000: Can't execute the given command because you have active locked tables or an active transaction
# UNLOCK TABLES so DROP SCHEMA can continue.
UNLOCK TABLES;
# Connection con2
# Connection default