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-- source include/have_innodb.inc
connect (con1,localhost,root,,);
connect (con2,localhost,root,,);
--disable_warnings
drop table if exists t1,t2;
--enable_warnings
#
# Testing of FOR UPDATE
#
connection con1;
create table t1 (id integer, x integer) type=INNODB;
insert into t1 values(0, 0);
set autocommit=0;
SELECT * from t1 where id = 0 FOR UPDATE;
connection con2;
set autocommit=0;
# The following query should hang because con1 is locking the page
--send
update t1 set x=2 where id = 0;
--sleep 2;
connection con1;
update t1 set x=1 where id = 0;
select * from t1;
commit;
connection con2;
reap;
commit;
connection con1;
select * from t1;
commit;
drop table t1;
#
# Testing of FOR UPDATE
#
connection con1;
create table t1 (id integer, x integer) type=INNODB;
create table t2 (b integer, a integer) type=INNODB;
insert into t1 values(0, 0), (300, 300);
insert into t2 values(0, 10), (1, 20), (2, 30);
commit;
set autocommit=0;
select * from t2;
update t2 set a=100 where b=(SELECT x from t1 where id = b FOR UPDATE);
select * from t2;
select * from t1;
connection con2;
set autocommit=0;
# The following query should hang because con1 is locking the page
--send
update t1 set x=2 where id = 0;
--sleep 2;
connection con1;
update t1 set x=1 where id = 0;
select * from t1;
commit;
connection con2;
reap;
commit;
connection con1;
select * from t1;
commit;
drop table t1, t2;
create table t1 (id integer, x integer) type=INNODB;
create table t2 (b integer, a integer) type=INNODB;
insert into t1 values(0, 0), (300, 300);
insert into t2 values(0, 0), (1, 20), (2, 30);
commit;
connection con1;
select a,b from t2 UNION SELECT id, x from t1 FOR UPDATE;
select * from t2;
select * from t1;
connection con2;
# The following query should hang because con1 is locking the page
update t2 set a=2 where b = 0;
select * from t2;
--send
update t1 set x=2 where id = 0;
--sleep 2;
connection con1;
update t1 set x=1 where id = 0;
select * from t1;
commit;
connection con2;
reap;
commit;
connection con1;
select * from t1;
commit;
drop table t1, t2;
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