如何在SQL 2005中删除属于特定表的所有默认约束?
答案 0 :(得分:7)
一个解决方案from a search :(编辑为默认约束)
SET NOCOUNT ON
DECLARE @constraintname SYSNAME, @objectid int,
@sqlcmd VARCHAR(1024)
DECLARE CONSTRAINTSCURSOR CURSOR FOR
SELECT NAME, object_id
FROM SYS.OBJECTS
WHERE TYPE = 'D' AND @objectid = OBJECT_ID('Mytable')
OPEN CONSTRAINTSCURSOR
FETCH NEXT FROM CONSTRAINTSCURSOR
INTO @constraintname, @objectid
WHILE (@@FETCH_STATUS = 0)
BEGIN
SELECT @sqlcmd = 'ALTER TABLE ' + OBJECT_NAME(@objectid) + ' DROP CONSTRAINT ' + @constraintname
EXEC( @sqlcmd)
FETCH NEXT FROM CONSTRAINTSCURSOR
INTO @constraintname, @objectid
END
CLOSE CONSTRAINTSCURSOR
DEALLOCATE CONSTRAINTSCURSOR
答案 1 :(得分:3)
我知道这是旧的,但我只是在谷歌上搜索它。 下面是一个解决方案,它适用于SQL 2008(不确定于2005年)而不依赖于游标:
declare @sql nvarchar(max)
set @sql = ''
select @sql = @sql + 'alter table YourTable drop constraint ' + name + ';'
from sys.default_constraints
where parent_object_id = object_id('YourTable')
AND type = 'D'
exec sp_executesql @sql
答案 2 :(得分:0)
gbn发布的脚本对我不起作用,所以我使用的是修改版本:
SET NOCOUNT ON
DECLARE @DfId INT, @TableId INT,
@SqlCmd VARCHAR(1024)
DECLARE DFCONSTRAINTCUR CURSOR FOR
SELECT [parent_object_id] TABLE_ID, [object_id] DF_ID
FROM SYS.OBJECTS
where parent_object_id = OBJECT_ID('<table name>')
and [TYPE] = 'D'
OPEN DFCONSTRAINTCUR
FETCH NEXT FROM DFCONSTRAINTCUR
INTO @TableId, @DfId
WHILE (@@FETCH_STATUS = 0)
BEGIN
SELECT @sqlcmd = 'ALTER TABLE ' + OBJECT_NAME(@TableId) + ' DROP CONSTRAINT ' + OBJECT_NAME(@DfId)
EXEC(@sqlcmd)
FETCH NEXT FROM DFCONSTRAINTCUR
INTO @TableId, @DfId
END
CLOSE DFCONSTRAINTCUR
DEALLOCATE DFCONSTRAINTCUR
答案 3 :(得分:-1)
你为什么要这样做?删除约束是一项非常激烈的操作,不仅会影响所有用户,还会影响您的流程。也许你的问题可以通过其他方式解决。如果你不是系统的dba,你应该认真考虑是否应该这样做。 (当然在大多数系统中,dba不允许任何其他人获得这样的权限。)