158 lines
3.2 KiB
Plaintext
158 lines
3.2 KiB
Plaintext
set @start_read_only= @@global.read_only;
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set @start_autocommit= @@global.autocommit;
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set @@global.autocommit= 0;
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CREATE USER test@localhost;
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grant CREATE, SELECT, UPDATE on *.* to test@localhost;
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CREATE USER test2@localhost;
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grant CREATE, SELECT, UPDATE on *.* to test2@localhost;
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connection default;
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CREATE TABLE t1 ( a INT, b INT) ENGINE=MyISAM;
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INSERT INTO t1 VALUES (1, 1);
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INSERT INTO t1 VALUES (2, 2);
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INSERT INTO t1 VALUES (3, 3);
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CREATE TABLE t2 ( a INT) ENGINE=InnoDB;
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INSERT INTO t2 VALUES (10);
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INSERT INTO t2 VALUES (20);
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INSERT INTO t2 VALUES (30);
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########################################################################
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# SELECT...FOR UPDATE:sequential search lock all rows as no key exists
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connect con1,localhost,test,,test;
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SET SESSION innodb_lock_wait_timeout=1;
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BEGIN;
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SELECT * FROM t2 WHERE a=20 FOR UPDATE ;
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a
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20
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connect con2,localhost,test2,,test;
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BEGIN;
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SET SESSION innodb_lock_wait_timeout=1;
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#
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# UPDATE ...
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SELECT * FROM t1 FOR UPDATE;
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a b
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1 1
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2 2
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3 3
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SELECT * FROM t1 FOR UPDATE NOWAIT;
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a b
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1 1
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2 2
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3 3
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SELECT * FROM t1 FOR UPDATE SKIP LOCKED;
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a b
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1 1
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2 2
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3 3
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#
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# SHARE ...
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SELECT * FROM t1 FOR SHARE;
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a b
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1 1
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2 2
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3 3
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SELECT * FROM t1 FOR SHARE NOWAIT;
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a b
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1 1
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2 2
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3 3
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SELECT * FROM t1 FOR SHARE SKIP LOCKED;
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a b
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1 1
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2 2
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3 3
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#
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# Dual locking clauses
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SELECT * FROM t1, t2 FOR SHARE OF t1 FOR UPDATE OF t2;
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ERROR HY000: Lock wait timeout exceeded; try restarting transaction
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SELECT * FROM t1, t2 FOR SHARE OF t1 FOR SHARE OF t2;
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ERROR HY000: Lock wait timeout exceeded; try restarting transaction
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SELECT * FROM t1 FOR SHARE OF t1 NOWAIT;
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a b
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1 1
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2 2
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3 3
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SELECT * FROM t1 FOR SHARE OF t1 SKIP LOCKED;
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a b
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1 1
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2 2
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3 3
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SELECT * FROM t1, t2 FOR SHARE OF t1 NOWAIT FOR SHARE OF t2 NOWAIT;
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ERROR HY000: Statement aborted because lock(s) could not be acquired immediately and NOWAIT is set.
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COMMIT;
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connection con1;
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commit;
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connection default;
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ALTER TABLE t2 ADD PRIMARY KEY (a);
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#######################################################################
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# SELECT ... FOR UPDATE is only locking row with a=2
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connection con1;
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BEGIN;
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SELECT * FROM t2 WHERE a=20 FOR UPDATE ;
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a
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20
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connection con2;
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BEGIN;
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SET SESSION innodb_lock_wait_timeout=1;
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#
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# UPDATE ...
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SELECT * FROM t1 FOR UPDATE;
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a b
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1 1
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2 2
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3 3
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SELECT * FROM t1 FOR UPDATE NOWAIT;
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a b
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1 1
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2 2
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3 3
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SELECT * FROM t1 FOR UPDATE SKIP LOCKED;
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a b
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1 1
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2 2
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3 3
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#
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# SHARE ...
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SELECT * FROM t1 FOR SHARE;
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a b
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1 1
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2 2
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3 3
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SELECT * FROM t1 FOR SHARE NOWAIT;
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a b
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1 1
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2 2
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3 3
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SELECT * FROM t1 FOR SHARE SKIP LOCKED;
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a b
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1 1
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2 2
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3 3
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#
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# Dual locking clauses
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SELECT * FROM t1, t2 FOR SHARE OF t1 FOR UPDATE OF t2;
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ERROR HY000: Lock wait timeout exceeded; try restarting transaction
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SELECT * FROM t1, t2 FOR SHARE OF t1 FOR SHARE OF t2;
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ERROR HY000: Lock wait timeout exceeded; try restarting transaction
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SELECT * FROM t1 FOR SHARE OF t1 NOWAIT;
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a b
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1 1
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2 2
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3 3
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SELECT * FROM t1 FOR SHARE OF t1 SKIP LOCKED;
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a b
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1 1
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2 2
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3 3
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SELECT * FROM t1, t2 FOR SHARE OF t1 NOWAIT FOR SHARE OF t2 NOWAIT;
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ERROR HY000: Statement aborted because lock(s) could not be acquired immediately and NOWAIT is set.
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COMMIT;
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connection con1;
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COMMIT;
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connection default;
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disconnect con1;
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disconnect con2;
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DROP TABLE t1, t2;
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DROP USER test@localhost;
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DROP USER test2@localhost;
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set @@global.read_only= @start_read_only;
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set @@global.autocommit= @start_autocommit;
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