原帖内容：
怎样把数据库中所有数据删除，然后把所有的自动增量复位？
表太多，无法手工完成。
http://community.csdn.net/Expert/topic/3094/3094555.xml?temp=.2920954
/*
--原本打算这样
--先禁用所有外键约束
exec sp_msforeachtable "alter table ? nocheck CONSTRAINT all"
--然后删除数据
exec sp_msforeachtable "truncate table ?"
--再启用所有外键约束
exec sp_msforeachtable "alter table ? check constraint all"
--但是禁用了以后，truncate table 不行，会提示冲突
*/
--现在我的想法是（语句待优化）：
--第一部分，生成建立外键的语句保存到#tmp
declare @name varchar(200),@tmp1 varchar(500),@tmp2 varchar(500)
create table #tmp
(
string varchar(8000)
)
SELECT 表名称=object_name(b.fkeyid)
,外键名称=a.name
,引用的列名=(SELECT name FROM syscolumns WHERE colid=b.fkey AND id=b.fkeyid)
,引用的表名=object_name(b.rkeyid)
,已引用的列名=(SELECT name FROM syscolumns WHERE colid=b.rkey AND id=b.rkeyid)
into #t FROM sysobjects a
join sysforeignkeys b on a.id=b.constid
join sysobjects c on a.parent_obj=c.id
where a.xtype='f' AND c.xtype='U'
declare cur_test cursor for
select a.name from sysobjects a join sysobjects c on a.parent_obj=c.id where a.xtype='f' and c.xtype='U'
open cur_test
FETCH NEXT FROM cur_test INTO @name
WHILE (@@fetch_status <> -1)
BEGIN
IF (@@fetch_status <> -2)
BEGIN
select @tmp1='',@tmp2=''
select @tmp1=@tmp1+'['+引用的列名+'],',@tmp2=@tmp2+'['+已引用的列名+'],' from #t where 外键名称=@name
insert into #tmp select top 1 'ALTER TABLE [DBO].['+表名称+'] ADD CONSTRAINT ['+@name+'] FOREIGN KEY ( '+left(@tmp1,len(@tmp1)-1)+' ) REFERENCES ['+引用的表名+'] ( '+left(@tmp2,len(@tmp2)-1)+' )' from #t where 外键名称=@name
END
FETCH NEXT FROM cur_test INTO @name
END
CLOSE cur_test
DEALLOCATE cur_test
drop table #t
--第二部分，删除所有外键
DECLARE @STRING VARCHAR(8000)
WHILE EXISTS(SELECT NAME FROM SYSOBJECTS WHERE TYPE='F')
BEGIN
SELECT @STRING='ALTER TABLE '+B.NAME+' DROP CONSTRAINT '+A.NAME+CHAR(13)
FROM (SELECT PARENT_OBJ,NAME FROM SYSOBJECTS WHERE TYPE='F') A,
(SELECT ID,NAME FROM SYSOBJECTS WHERE OBJECTPROPERTY(ID, N'ISUSERTABLE') = 1) B
WHERE A.PARENT_OBJ=B.ID
EXEC(@STRING)
END
--第三部分，删除所有表的记录，并且把identity复位
exec sp_msforeachtable "truncate table ?"
--第4部分，执行#tmp里面的建立外键的语句，恢复外键
declare cur_test2 cursor for select string from #tmp
open cur_test2
FETCH NEXT FROM cur_test2 INTO @string
WHILE (@@fetch_status <> -1)
BEGIN
IF (@@fetch_status <> -2)
BEGIN
exec(@string)
PRINT @STRING
END
FETCH NEXT FROM cur_test2 INTO @string
END
CLOSE cur_test2
DEALLOCATE cur_test2
drop table #tmp
