删除数据库中的所有的数据，保留一个库的结构，其中很多表多是做了关联的！(整理自IT PUB)

熱心的朋友提供了很多方法﹕
A﹑最簡便的方法﹕
1建一个目标空库，做DTS，选择只复制结构。
2生成数据库的脚本，如图，然后可以建一个同名空库恢复。


B﹑利用存儲過程﹕
create proc up_010
as
begin
declare @sql varchar(99),@tbl varchar(30),@fk varchar(30)
declare cur_fk cursor local for
select object_name(constid),object_name(fkeyid) from sysreferences
--删除所有外键
open cur_fk
fetch cur_fk into @fk,@tbl
while @@fetch_status =0
begin
set @sql='alter table '+@tbl+' nocheck constraint '+@fk
exec(@SQL)
fetch cur_fk into @fk,@tbl
end
close cur_fk
deallocate cur_fk
--删除数据
declare @times int
set @times=10
while @times<>0
begin
declare cur_fks cursor local for
select name from sysobjects where xtype='U'
open cur_fks
fetch cur_fks into @tbl
while @@fetch_status =0
begin
select @sql='delete from ['+@tbl+']'
exec(@SQL)
fetch cur_fks into @tbl
end
close cur_fks
deallocate cur_fks
set @times=@times-1
end
--增加所以的外键
declare addcur_fk cursor local for
select object_name(constid),object_name(fkeyid) from sysreferences
open addcur_fk
fetch addcur_fk into @fk,@tbl
while @@fetch_status=0
begin
set @sql='alter table '+@tbl+' check constraint '+@fk
exec(@sql)
fetch addcur_fk into @fk,@tbl
end
close addcur_fk
deallocate addcur_fk
--
end
go

C﹑
/*
--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

go

D﹑

sp_MSforeachtable是简单些,能用系统的提供的最好.虽然它也是用游标来执行,应该更有效吧!