实验记录
打开两个session
set innodb_lock_wait_timeout=5; 设置 Lock wait timeout exceeded 为5秒，这样等待被锁阻塞的时间能短点 -_-! 便于实验进行
表结构
其中id为主键；age为普通索引
in name age
1 name1 15
5 lucy 18
11 南风 22
15 洛神赋 28
存在的非唯一索引
-
select * from user where age = 22 for update;
锁住[18,28] -
select * from user where age > 22 for update;
锁住[22,+x] -
select * from user where age < 22 for update;
锁住[-x,22)
不存在的非唯一索引
-
select * from user where age = 20 for update;
锁住[18,22) -
select * from user where age < 20 for update;
锁住(-x,22) -
select * from user where age > 20 for update;
锁住[18,+x)
非唯一索引区间
- select * from user where age > 17 and age < 23 for update;
锁住[15,28)
存在的唯一索引记录
-
select * from user where id = 11 for update;
锁住11（只有record锁） -
select * from user where id > 11 for update;
锁住(11,+x) -
select * from user where id < 11 for update;
锁住(-x,11]
不存在的唯一索引记录
-
select * from user where id = 10 for update;
锁住(5,11) -
select * from user where id > 10 for update;
锁住(5,+x) -
select * from user where id < 10 for update;
锁住(-x,11)
唯一索引左右区间
-
select * from user where id > 10 and id < 12 for update;
锁住(5,15] -
select * from user where id > 3 and id < 12 for update;
锁住(1,15]
