SET @save_timeout=@@GLOBAL.innodb_lock_wait_timeout; SET GLOBAL innodb_lock_wait_timeout=100000000; DESCRIBE INFORMATION_SCHEMA.INNODB_TRX; Field Type Null Key Default Extra trx_id bigint(21) unsigned NO NULL trx_state varchar(13) NO NULL trx_started datetime NO NULL trx_requested_lock_id varchar(81) YES NULL trx_wait_started datetime YES NULL trx_weight bigint(21) unsigned NO NULL trx_mysql_thread_id bigint(21) unsigned NO NULL trx_query varchar(1024) YES NULL trx_operation_state varchar(64) YES NULL trx_tables_in_use bigint(21) unsigned NO NULL trx_tables_locked bigint(21) unsigned NO NULL trx_lock_structs bigint(21) unsigned NO NULL trx_lock_memory_bytes bigint(21) unsigned NO NULL trx_rows_locked bigint(21) unsigned NO NULL trx_rows_modified bigint(21) unsigned NO NULL trx_concurrency_tickets bigint(21) unsigned NO NULL trx_isolation_level enum('READ UNCOMMITTED','READ COMMITTED','REPEATABLE READ','SERIALIZABLE') NO NULL trx_unique_checks int(1) NO NULL trx_foreign_key_checks int(1) NO NULL trx_last_foreign_key_error varchar(256) YES NULL trx_is_read_only int(1) NO NULL trx_autocommit_non_locking int(1) NO NULL CREATE TABLE t1 ( c01 INT, c02 INT, PRIMARY KEY (c01) ) ENGINE=INNODB STATS_AUTO_RECALC=0; INSERT INTO t1 VALUES (1,2),(2,4),(3,6),(4,8); CREATE TABLE t2 ( c01 INT, c02 INT, PRIMARY KEY (c01), FOREIGN KEY fk1 (c02) REFERENCES t1 (c01) ) ENGINE=INNODB STATS_AUTO_RECALC=0; INSERT INTO t2 VALUES (1,1),(2,2),(3,3); connect con_trx,localhost,root,,; connect con_verify_innodb_trx,localhost,root,,; connection con_trx; SET autocommit=0; INSERT INTO t1 VALUES (5,10); SELECT * FROM t1 FOR UPDATE; c01 c02 1 2 2 4 3 6 4 8 5 10 connection con_verify_innodb_trx; SELECT trx_state, trx_weight, trx_tables_in_use, trx_tables_locked, trx_rows_locked, trx_rows_modified, trx_concurrency_tickets, trx_isolation_level, trx_unique_checks, trx_foreign_key_checks FROM INFORMATION_SCHEMA.INNODB_TRX; trx_state trx_weight trx_tables_in_use trx_tables_locked trx_rows_locked trx_rows_modified trx_concurrency_tickets trx_isolation_level trx_unique_checks trx_foreign_key_checks RUNNING 3 0 1 6 1 0 REPEATABLE READ 1 1 connection con_trx; ROLLBACK; SET FOREIGN_KEY_CHECKS = 0; SET UNIQUE_CHECKS = 0; SET TRANSACTION ISOLATION LEVEL SERIALIZABLE; BEGIN; INSERT INTO t1 VALUES (6,12); connection con_verify_innodb_trx; SELECT trx_isolation_level, trx_unique_checks, trx_foreign_key_checks FROM INFORMATION_SCHEMA.INNODB_TRX; trx_isolation_level trx_unique_checks trx_foreign_key_checks SERIALIZABLE 0 0 connection con_trx; ROLLBACK; SET FOREIGN_KEY_CHECKS = 1; SET UNIQUE_CHECKS = 1; BEGIN; INSERT INTO t2 VALUES (4,10); ERROR 23000: Cannot add or update a child row: a foreign key constraint fails (`test`.`t2`, CONSTRAINT `fk1` FOREIGN KEY (`c02`) REFERENCES `t1` (`c01`)) disconnect con_trx; connection con_verify_innodb_trx; SELECT trx_state, trx_isolation_level, trx_last_foreign_key_error FROM INFORMATION_SCHEMA.INNODB_TRX; trx_state trx_isolation_level trx_last_foreign_key_error RUNNING REPEATABLE READ `test`.`t2`, CONSTRAINT `fk1` FOREIGN KEY (`c02`) REFERENCES `t1` (`c01`) disconnect con_verify_innodb_trx; connection default; DROP TABLE t2; DROP TABLE t1; SET GLOBAL innodb_lock_wait_timeout=@save_timeout;