去除外键的存储过程

create proce prdropforeignkeys
@chvreferencedtable varchar(30)
as
 declare @chvtablewithforeignkey varchar(30),
 @chvforeignkey varchar(30),
 @chvsql varchar(255)
declare cufks cursor for 
 select tb.name,fk.name from 
((sysobject tb inner join sysreferences r on tb.id=r.fkeyid)
 inner join sysobjects fk on r.constid=fk.id)
 inner join sysobjects refd on refd_tb.id=r.rkeyid)
 where refd_tb.name=@chvreferencedtable
 open cufks
 fetch next from cufks into @chvtablewithforeignkey,@chvforeignkey 

 while (@@fetch_status<>-1)
 begin
 select @chvsql='alter table'+@chvtablewithforeignkey+
 'drop constraint '+@chvforeignkey
 exec(@chvsql)
 fetch next from cufks into @chvtablewithforeignkey,@chvforeignkey
end
 deallocate cufks