mysql的事务运作 mysql的事务运作 早就想写了,一直忘了,其实很简单 就三条命令 start transaction commit rollback 现在来解释下: start transaction; 就是开始事务追踪的命令 开始前一定记得写 然后 commit; 这个的意思是说确认提交,执行这个命令就不能r
mysql的事务运作mysql的事务运作
早就想写了,一直忘了,其实很简单
-
就三条命令
start transaction
commit
rollback -
现在来解释下:
start transaction;
就是开始事务追踪的命令
开始前一定记得写然后
commit;
这个的意思是说确认提交,执行这个命令就不能rollback了,相当于执行完毕。最后
rollback;
这个命令很简单,回滚到start transaction时候的状态 -
现在举例
mysql> select * from useraccount ;
+-----------+--------+-------------+
| AccountID | userID | AccountName |
+-----------+--------+-------------+
| 1 | 2 | zhifubao |
+-----------+--------+-------------+
1 row in set (0.00 sec)mysql> start transaction;
Query OK, 0 rows affected (0.00 sec)mysql> update useraccount set userID = 1;
Query OK, 1 row affected (0.00 sec)
Rows matched: 1 Changed: 1 Warnings: 0mysql> select * from useraccount;
+-----------+--------+-------------+
| AccountID | userID | AccountName |
+-----------+--------+-------------+
| 1 | 1 | zhifubao |
+-----------+--------+-------------+
1 row in set (0.00 sec)mysql> rollback; (这里假如不想回滚就用commit;就可以完成了)
Query OK, 0 rows affected (0.28 sec)mysql> select * from useraccount;
+-----------+--------+-------------+
| AccountID | userID | AccountName |
+-----------+--------+-------------+
| 1 | 2 | zhifubao |
+-----------+--------+-------------+
1 row in set (0.00 sec)

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