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drop table if exists t1;
connect a,localhost,root,,;
connect b,localhost,root,,;
connection a;
set binlog_format=mixed;
set session transaction isolation level repeatable read;
create table t1(a int not null)
engine=innodb
DEFAULT CHARSET=latin1
PARTITION BY RANGE(a)
(PARTITION p0 VALUES LESS THAN (20),
PARTITION p1 VALUES LESS THAN MAXVALUE);
insert into t1 values (1),(2),(3),(4),(5),(6),(7);
set autocommit=0;
select * from t1 where a=3 lock in share mode;
a
3
connection b;
set binlog_format=mixed;
set innodb_snapshot_isolation=OFF;
set session transaction isolation level repeatable read;
set autocommit=0;
update t1 set a=10 where a=5;
ERROR HY000: Lock wait timeout exceeded; try restarting transaction
commit;
connection a;
commit;
connection b;
set session transaction isolation level read committed;
update t1 set a=10 where a=5;
connection a;
select * from t1 where a=2 for update;
ERROR HY000: Lock wait timeout exceeded; try restarting transaction
select * from t1 where a=2 limit 1 for update;
a
2
connection b;
update t1 set a=11 where a=6;
update t1 set a=12 where a=2;
ERROR HY000: Lock wait timeout exceeded; try restarting transaction
update t1 set a=13 where a=1;
ERROR HY000: Lock wait timeout exceeded; try restarting transaction
connection a;
commit;
connection b;
update t1 set a=14 where a=1;
commit;
connection a;
select * from t1;
a
10
11
14
2
3
4
7
drop table t1;
connection default;
disconnect a;
disconnect b;
connect con1,localhost,root,,;
connect con2,localhost,root,,;
SET SESSION AUTOCOMMIT = 0;
SET SESSION TRANSACTION ISOLATION LEVEL READ COMMITTED;
set binlog_format=mixed;
connection con1;
CREATE TABLE t1 (a INT PRIMARY KEY, b VARCHAR(256))
ENGINE = InnoDB
PARTITION BY RANGE (a)
(PARTITION p0 VALUES LESS THAN (300),
PARTITION p1 VALUES LESS THAN MAXVALUE);
INSERT INTO t1 VALUES (1,2);
# 1. test for locking:
BEGIN;
UPDATE t1 SET b = 12 WHERE a = 1;
affected rows: 1
info: Rows matched: 1 Changed: 1 Warnings: 0
SELECT * FROM t1;
a b
1 12
connection con2;
UPDATE t1 SET b = 21 WHERE a = 1;
ERROR HY000: Lock wait timeout exceeded; try restarting transaction
ROLLBACK;
connection con1;
SELECT * FROM t1;
a b
1 12
ROLLBACK;
# 2. test for serialized update:
CREATE TABLE t2 (a INT);
TRUNCATE t1;
INSERT INTO t1 VALUES (1,'init');
CREATE PROCEDURE p1()
BEGIN
# retry the UPDATE in case it times out the lock before con1 has time
# to COMMIT.
DECLARE do_retry INT DEFAULT 0;
DECLARE CONTINUE HANDLER FOR SQLEXCEPTION SET do_retry = 1;
retry_loop:LOOP
UPDATE t1 SET b = CONCAT(b, '+con2') WHERE a = 1;
IF do_retry = 0 THEN
LEAVE retry_loop;
END IF;
SET do_retry = 0;
END LOOP;
INSERT INTO t2 VALUES ();
END|
BEGIN;
UPDATE t1 SET b = CONCAT(b, '+con1') WHERE a = 1;
affected rows: 1
info: Rows matched: 1 Changed: 1 Warnings: 0
SELECT * FROM t1;
a b
1 init+con1
connection con2;
CALL p1;;
connection con1;
SELECT * FROM t1;
a b
1 init+con1
COMMIT;
SELECT * FROM t1;
a b
1 init+con1
connection con2;
SELECT * FROM t1;
a b
1 init+con1+con2
COMMIT;
connection con1;
# 3. test for updated key column:
TRUNCATE t1;
DELETE FROM t2;
INSERT INTO t1 VALUES (1,'init');
BEGIN;
UPDATE t1 SET a = 2, b = CONCAT(b, '+con1') WHERE a = 1;
affected rows: 1
info: Rows matched: 1 Changed: 1 Warnings: 0
SELECT * FROM t1;
a b
2 init+con1
connection con2;
CALL p1;;
connection con1;
SELECT * FROM t1;
a b
2 init+con1
COMMIT;
SELECT * FROM t1;
a b
2 init+con1
connection con2;
SELECT * FROM t1;
a b
2 init+con1
connection default;
disconnect con1;
disconnect con2;
DROP PROCEDURE p1;
DROP TABLE t1, t2;
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