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fix mispell, strongest compulsively

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kwongtai 2018-04-13 18:55:05 +08:00
parent 7665cac1dc
commit f04af8ccf0
1 changed files with 3 additions and 3 deletions
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6
notes/数据库系统原理.md
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@ -227,13 +227,13 @@ MySQL 中提供了两种封锁粒度：行级锁以及表级锁。
事务遵循两段锁协议是保证并发操作可串行化调度的充分条件。例如以下操作满足两段锁协议，它是可串行化调度。
```html
lock-x(A)...lock-s(B)...lock-s(c)...unlock(A)...unlock(C)...unlock(B)
lock-x(A)...lock-s(B)...lock-s(C)...unlock(A)...unlock(C)...unlock(B)
```
但不是必要条件，例如以下操作不满足两段锁协议，但是它还是可串行化调度。
```html
lock-x(A)...unlock(A)...lock-s(B)...unlock(B)...lock-s(c)...unlock(C)...
lock-x(A)...unlock(A)...lock-s(B)...unlock(B)...lock-s(C)...unlock(C)...
```
# 四、隔离级别
@ -331,7 +331,7 @@ select * from table ....;
select * from table where ? lock in share mode;
select * from table where ? for update;
insert;
update ;
update;
delete;
```