A simple SQL Injection Attack

In the previous blog: http://blog.csdn.net/suwei19870312/article/details/7579667. This section describes the interaction between client code and server code.

The client code passes a parameter q to the server code user. php through the get method,

In the user. PHP code, use the parameter q to construct an SQL statement for accessing the database:

1. $ SQL = "select * from user where id = '". $ Q ."'";
2. $ Result = mysql_query ($ SQL );

If the parameter q = "'or '1' = '1" passed by the client at this time ",

In this case, the SQL statement becomes "select * from user where id ='' or '1' = '1 '"

In this case, all data in the User table is returned.

This is an example of a simple SQL injection attack.

Http://zh.wikipedia.org/wiki/ SQL %E8%B3%87%E6%96%99%E9%9A%B1%E7%A2%BC%E6%94%BB%E6%93%8A

Http://baike.baidu.com/view/983303.htm