测试环境：MySQL 5.7.26创建测试表：
mysql> create table t4(id int,name varchar(10),primary key(id),unique key(name)); Query OK, 0 rows affected (0.01 sec)
插入测试数据：
mysql> insert into t4 values(1,'aaa'); Query OK, 1 row affected (0.00 sec) mysql> insert into t4 values(2,'bbb'); Query OK, 1 row affected (0.00 sec)
模拟死锁过程：
过程说明：
查看死锁日志：
LATEST DETECTED DEADLOCK ------------------------ 2020-08-21 18:45:50 0x7f38f84d3700 *** (1) TRANSACTION: TRANSACTION 26176862, ACTIVE 17 sec starting index read mysql tables in use 1, locked 1 LOCK WAIT 2 lock struct(s), heap size 1136, 1 row lock(s) MySQL thread id 208, OS thread handle 139883056465664, query id 3863533 localhost root updating delete from t4 where name='aaa' *** (1) WAITING FOR THIS LOCK TO BE GRANTED: RECORD LOCKS space id 834 page no 4 n bits 72 index name of table `test`.`t4` trx id 26176862 lock_mode X locks rec but not gap waiting Record lock, heap no 2 PHYSICAL RECORD: n_fields 2; compact format; info bits 32 0: len 3; hex 616161; asc aaa;; 1: len 4; hex 80000001; asc ;; *** (2) TRANSACTION: TRANSACTION 26176839, ACTIVE 28 sec inserting, thread declared inside InnoDB 5000 mysql tables in use 1, locked 1 4 lock struct(s), heap size 1136, 3 row lock(s), undo log entries 2 MySQL thread id 209, OS thread handle 139882660706048, query id 3863602 localhost root update insert into t4 values(3,'aaa') *** (2) HOLDS THE LOCK(S): RECORD LOCKS space id 834 page no 4 n bits 72 index name of table `test`.`t4` trx id 26176839 lock_mode X locks rec but not gap Record lock, heap no 2 PHYSICAL RECORD: n_fields 2; compact format; info bits 32 0: len 3; hex 616161; asc aaa;; 1: len 4; hex 80000001; asc ;; *** (2) WAITING FOR THIS LOCK TO BE GRANTED: RECORD LOCKS space id 834 page no 4 n bits 72 index name of table `test`.`t4` trx id 26176839 lock mode S waiting Record lock, heap no 2 PHYSICAL RECORD: n_fields 2; compact format; info bits 32 0: len 3; hex 616161; asc aaa;; 1: len 4; hex 80000001; asc ;; *** WE ROLL BACK TRANSACTION (1)
