drop table if exists t1; 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 set binlog_format=mixed; 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; set session transaction isolation level read committed; update t1 set a=10 where a=5; 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 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 commit; update t1 set a=14 where a=1; commit; select * from t1; a 10 11 14 2 3 4 7 drop table t1; SET SESSION AUTOCOMMIT = 0; SET SESSION TRANSACTION ISOLATION LEVEL READ COMMITTED; set binlog_format=mixed; # Switch to 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 # Switch to connection con2 UPDATE t1 SET b = 21 WHERE a = 1; ERROR HY000: Lock wait timeout exceeded; try restarting transaction # Switch to 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 UPDATE t1 SET b = CONCAT(b, '+con2') WHERE a = 1; 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 # Switch to connection con2 CALL p1;; # Switch to connection con1 SELECT * FROM t1; a b 1 init+con1 COMMIT; SELECT * FROM t1; a b 1 init+con1 # Switch to connection con2 SELECT * FROM t1; a b 1 init+con1+con2 # Switch to connection con1 # 3. test for updated key column: TRUNCATE t1; TRUNCATE 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 # Switch to connection con2 CALL p1;; # Switch to connection con1 SELECT * FROM t1; a b 2 init+con1 COMMIT; SELECT * FROM t1; a b 2 init+con1 # Switch to connection con2 SELECT * FROM t1; a b 2 init+con1 DROP PROCEDURE p1; DROP TABLE t1, t2;