我们可以在mysql事务处理过程中定义保存点(SAVEPOINT)，然后回滚到指定的保存点前的状态。

定义保存点，以及回滚到指定保存点前状态的语法如下。

定义保存点---SAVEPOINT 保存点名;

回滚到指定保存点---ROLLBACK TO SAVEPOINT 保存点名:

下面演示将向表user中连续插入3条数据，在插入第2条数据的后面定义一个保存点，最后看看能否回滚到此保存点。

1、查看user表中的数据

mysql> select * from user;

+-----+----------+-----+------+

| mid | name | scx | word |

+-----+----------+-----+------+

| 1 | zhangsan | 0 | NULL |

| 2 | wangwu    | 1 | NULL |

+-----+----------+-----+------+

2 rows in set (0.05 sec)

2、mysql事务开始

mysql> BEGIN;

Query OK, 0 rows affected (0.00 sec)

3、向表user中插入2条数据

mysql> INSERT INTO user VALUES ('3','one','0','');

Query OK, 1 row affected (0.08 sec)

mysql> INSERT INTO user VALUES ('4,'two','0','');

Query OK, 1 row affected (0.00 sec)

mysql> select * from user;

+-----+----------+-----+------+

| mid | name | scx | word |

+-----+----------+-----+------+

| 1 | zhangsan | 0 | NULL |

| 2 | wangwu    | 1 | NULL |

| 3 | one            | 0 | |

| 4 | two             | 0 | |

+-----+----------+-----+------+

4 rows in set (0.00 sec)

4、指定保存点，保存点名为test

mysql> SAVEPOINT test;

Query OK, 0 rows affected (0.00 sec)

5、向表user中插入第3条数据

mysql> INSERT INTO user VALUES ('5','three','0','');

Query OK, 1 row affected (0.00 sec)

mysql> select * from user;

+-----+----------+-----+------+

| mid | name | scx | word |

+-----+----------+-----+------+

| 1 | zhangsan | 0 | NULL |

| 2 | wangwu | 1 | NULL |

| 3 | one | 0 | |

| 4 | two | 0 | |

| 5 | three | 0 | |

+-----+----------+-----+------+

5 rows in set (0.02 sec)

6、回滚到保存点test

mysql> ROLLBACK TO SAVEPOINT test;

Query OK, 0 rows affected (0.31 sec)

mysql> select * from user;

+-----+----------+-----+------+

| mid | name | scx | word |

+-----+----------+-----+------+

| 1 | zhangsan | 0 | NULL |

| 2 | wangwu    | 1 | NULL |

| 3 | one            | 0 | |

| 4 | two            | 0 | |

+-----+----------+-----+------+

4 rows in set (0.00 sec)

我们可以看到保存点test以后插入的记录没有显示了，即成功团滚到了定义保存点test前的状态。利用保存点可以实现只提交事务中部分处理的功能。