2003-01-06 00:48:59 +01:00
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drop table if exists t1,t2;
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2003-12-10 05:31:42 +01:00
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create table t1 (id integer, x integer) engine=INNODB;
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2002-11-24 20:39:22 +01:00
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insert into t1 values(0, 0);
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set autocommit=0;
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SELECT * from t1 where id = 0 FOR UPDATE;
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id x
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0 0
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set autocommit=0;
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update t1 set x=2 where id = 0;
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update t1 set x=1 where id = 0;
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select * from t1;
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id x
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0 1
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commit;
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commit;
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select * from t1;
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id x
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0 2
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commit;
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drop table t1;
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2003-12-10 05:31:42 +01:00
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create table t1 (id integer, x integer) engine=INNODB;
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create table t2 (b integer, a integer) engine=INNODB;
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2002-11-25 17:34:24 +01:00
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insert into t1 values(0, 0), (300, 300);
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insert into t2 values(0, 10), (1, 20), (2, 30);
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commit;
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set autocommit=0;
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select * from t2;
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b a
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0 10
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1 20
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2 30
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update t2 set a=100 where b=(SELECT x from t1 where id = b FOR UPDATE);
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select * from t2;
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b a
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0 100
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1 20
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2 30
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select * from t1;
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id x
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0 0
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300 300
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set autocommit=0;
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update t1 set x=2 where id = 0;
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update t1 set x=1 where id = 0;
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select * from t1;
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id x
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0 1
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300 300
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commit;
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commit;
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select * from t1;
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id x
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0 2
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300 300
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commit;
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drop table t1, t2;
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2003-12-10 05:31:42 +01:00
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create table t1 (id integer, x integer) engine=INNODB;
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create table t2 (b integer, a integer) engine=INNODB;
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2002-11-25 17:34:24 +01:00
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insert into t1 values(0, 0), (300, 300);
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insert into t2 values(0, 0), (1, 20), (2, 30);
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commit;
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select a,b from t2 UNION SELECT id, x from t1 FOR UPDATE;
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a b
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0 0
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20 1
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30 2
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300 300
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select * from t2;
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b a
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0 0
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1 20
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2 30
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select * from t1;
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id x
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0 0
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300 300
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update t2 set a=2 where b = 0;
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select * from t2;
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b a
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0 2
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1 20
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2 30
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update t1 set x=2 where id = 0;
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update t1 set x=1 where id = 0;
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select * from t1;
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id x
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0 1
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300 300
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commit;
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commit;
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select * from t1;
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id x
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0 2
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300 300
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commit;
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drop table t1, t2;
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