MySQL transaction

MySQL事务操作

1. 事务rollback

   mysql> start transaction;

   Query OK, 0 rows affected (0.00 sec)

    

   mysql> insert into tbtest(stu_ID,stu_Name) values(201,'stu_1');

   Query OK, 1 row affected (0.04 sec)

    

   mysql> select * from tbtest;

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

   | stu_ID | stu_Name | stu_test |

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

   | 123 | xiaoMing | NULL |

   | 124 | xiaoZhang | NULL |

   | 125 | xiaoLi | NULL |

   | 201 | stu_1 | NULL |

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

   4 rows in set (0.00 sec)

    

   mysql> rollback;

   Query OK, 0 rows affected (0.06 sec)

    

   mysql> select * from tbtest;

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

   | stu_ID | stu_Name | stu_test |

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

   | 123 | xiaoMing | NULL |

   | 124 | xiaoZhang | NULL |

   | 125 | xiaoLi | NULL |

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

   3 rows in set (0.00 sec)

    

   mysql> rollback;

   Query OK, 0 rows affected (0.00 sec)

    

2. 事务commit

   mysql> start transaction;

   Query OK, 0 rows affected (0.00 sec)

    

   mysql> insert into tbtest(stu_ID,stu_Name) values(201,'stu_1');

   Query OK, 1 row affected (0.00 sec)

    

   mysql> select * from tbtest;

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

   | stu_ID | stu_Name | stu_test |

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

   | 123 | xiaoMing | NULL |

   | 124 | xiaoZhang | NULL |

   | 125 | xiaoLi | NULL |

   | 201 | stu_1 | NULL |

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

   4 rows in set (0.00 sec)

    

   mysql> commit;

   Query OK, 0 rows affected (0.02 sec)

    

   mysql> select * from tbtest;

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

   | stu_ID | stu_Name | stu_test |

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

   | 123 | xiaoMing | NULL |

   | 124 | xiaoZhang | NULL |

   | 125 | xiaoLi | NULL |

   | 201 | stu_1 | NULL |

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

   4 rows in set (0.00 sec)

    

3. 计算上一条语句影响了多少行的两个相关函数

MySQL 有两个函数来计算上一条语句影响了多少行

1. found_rows()

判断Select得到的行数用 found_rows();

 

mysql> select * from tbtest;

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

| stu_ID | stu_Name | stu_test |

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

| 123 | xiaoMing | NULL |

| 124 | xiaoZhang | NULL |

| 125 | xiaoLi | NULL |

| 201 | stu_1 | NULL |

| 202 | stu_2 | NULL |

| 203 | stu_3 | NULL |

| 204 | stu_4 | NULL |

| 205 | stu_4 | NULL |

| 206 | stu_4 | NULL |

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

9 rows in set (0.00 sec)

mysql> select found_rows();

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

| found_rows() |

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

| 9 |

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

1 row in set (0.00 sec)

1. row_count()

判断Update Delete影响的行数用row_count(); 注：MySQL中Update前后的值如果一样，row_count()为0，不像在SqlServer中的@@rowcount/Oracle中的rowcount,只要update到行，影响的行数就会大于0(无论前后字段的值是否发生了变化)

mysql> insert into tbtest(stu_id, stu_name) values(207, 'stu_46');

Query OK, 1 row affected (0.02 sec)

mysql> select row_count();

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

| row_count() |

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

| 1 |

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

1 row in set (0.00 sec)