數據庫一些刪除語句

--1.刪除外鍵約束
DECLARE c1 cursor for
    select 'alter table ['+ object_name(parent_obj) + '] drop constraint ['+name+']; '
    from sysobjects
    where xtype = 'F'
open c1
declare @c1 varchar(8000)
fetch next from c1 into @c1
while(@@fetch_status=0)
    begin
        exec(@c1)
        fetch next from c1 into @c1
    end
close c1
deallocate c1

--2.刪除表
DECLARE c2 cursor for
    select 'drop table ['+name +']; '
    from sysobjects
    where xtype = 'u'
open c2
declare @c2 varchar(8000)
fetch next from c2 into @c2
while(@@fetch_status=0)
    begin
        exec(@c2)
        fetch next from c2 into @c2 
    end
close c2
deallocate c2

--批量清除表內容：

--1.禁用外鍵約束
DECLARE c1 cursor for
    select 'alter table ['+ object_name(parent_obj) + '] nocheck constraint ['+name+']; '
    from sysobjects
    where xtype = 'F'
open c1
declare @c1 varchar(8000)
fetch next from c1 into @c1
while(@@fetch_status=0)
    begin
        exec(@c1)
        fetch next from c1 into @c1
    end
close c1
deallocate c1

--2.清除表內容
DECLARE c2 cursor for
    select 'truncate table ['+name +']; '
    from sysobjects
    where xtype = 'u'
open c2
declare @c2 varchar(8000)
fetch next from c2 into @c2
while(@@fetch_status=0)
    begin
        exec(@c2)
        fetch next from c2 into @c2
    end
close c2
deallocate c2

--3.啓用外鍵約束
DECLARE c1 cursor for
    select 'alter table ['+ object_name(parent_obj) + '] check constraint ['+name+']; '
    from sysobjects
    where xtype = 'F'
open c1
declare @c1 varchar(8000)
fetch next from c1 into @c1
while(@@fetch_status=0)
    begin
        exec(@c1)
        fetch next from c1 into @c1
    end
close c1
deallocate c1