删除表字段的sql语句
哎,还是上周的事情了,csdn的博客最近咋老是打不开呢!
基本语句:Alter table 表名 drop Column 字段名
另单单是这样是不行滴,还要删除对应的关系滴。下面就把查找到的那篇文章引用下吧!
原文地址:http://hi.baidu.com/lisky119/blog/item/3c348c082573949c0a7b82d1.html
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
-- =============================================
-- Author: lw
-- Create date: 2009-07-31
-- Description: 强行删除表列,【无错误】【删除表的列之前一定要删除依赖,索引】,不然会报很多错误
-- =============================================
alter PROCEDURE [dbo].[Delete_Column_Constraint]
(
@tablename nvarchar(50),
@columnname nvarchar(50)
)
AS
--删除某字段的所有关系
declare tb cursor local for
--默认值约束
select sql='alter table ['+b.name+'] drop constraint ['+d.name+']'
from syscolumns a
join sysobjects b on a.id=b.id
join syscomments c on a.cdefault=c.id
join sysobjects d on c.id=d.id
where b.name = @tablename
and a.name = @columnname
union all --外键引用
select s='alter table ['+c.name+'] drop constraint ['+b.name+']'
from sysforeignkeys a
join sysobjects b on b.id=a.constid
join sysobjects c on c.id=a.fkeyid
join syscolumns d on d.id=c.id and
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