SQLServer 删除所有表的外键约束

DECLARE c1 cursor for    
select 'alter table ['+ object_name(parent_obj) + '] drop constraint ['+name+']; '   
from sysobjects     
where xtype = 'F'
open c1declare @c1 varchar(8000)
fetch next from c1 into @c1while(@@fetch_status=0)  
begin        
exec(@c1)       
fetch next from c1 into @c1    
endclose 
c1deallocate c1