软件开发培训班 >> 编程开发 >> MySQL


MySQL数据库防止人为误操作的实例讲解

　　本文标签：MySQL数据库,误操作

有不少开发人员在操作MySQL数据库的时候都遇到过误操作的情况，例如更新数据库的时候update语句忘记加上where条件，就会造成极为悲剧的结果 。本文就针对防止MySQL数据库误操作的方法做出如下详解：

1、mysql帮助说明

# mysql --help|grep dummy  
 -U, --i-am-a-dummy Synonym for option --safe-updates, -U. 
i-am-a-dummy  FALSE

在mysql命令加上选项-U后，当发出没有WHERE或LIMIT关键字的UPDATE或DELETE时，mysql程序就会拒绝执行

2、指定-U登录测试

# mysql -uroot -poldboy123 -S /data/3306/mysql.sock -U 
Welcome to the MySQL monitor. Commands end with ; or \g. 
Your MySQL connection id is 14 
Server version: 5.5.32-log MySQL Community Server (GPL) 
Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved. 
Oracle is a registered trademark of Oracle Corporation and/or its 
affiliates. Other names may be trademarks of their respective 
owners. 
Type help; or \h for help. Type \c to clear the current input statement. 
mysql> delete from oldboy.student; 
ERROR 1175 (HY000): You are using safe update mode and you tried to update a table without a WHERE that uses a KEY column 
mysql> quit 
Bye

提示：此处不加条件无法删除，目的达到 。

3、做成别名防止DBA误操作

# alias mysql=mysql -U 
# mysql -uroot -poldboy123 -S /data/3306/mysql.sock 
Welcome to the MySQL monitor. Commands end with ; or \g. 
Your MySQL connection id is 15 
Server version: 5.5.32-log MySQL Community Server (GPL) 
Type help; or \h for help. Type \c to clear the current input statement. 
mysql> delete from oldboy.student; 
ERROR 1175 (HY000): You are using safe update mode and you tried to update a table without a WHERE that uses a KEY column 
mysql> delete from oldboy.student where Sno=5; 
Query OK, 1 row affected (0.02 sec) 
mysql> quit 
Bye 
# echo "alias mysql=mysql -U" >>/etc/profile 
# . /etc/profile 
# tail -1 /etc/profile 
alias mysql=mysql -U

结论：在mysql命令加上选项-U后，当发出没有WHERE或LIMIT关键字的UPDATE或DELETE时，mysql程序拒绝执行