触发器和游标的第一次使用

Create TRIGGER tg_bcnum ON [dbo].[mps_comment] AFTER Insert,delete    NOT FOR REPLICATIONAS    IF Update (c_id)        declare @orderN varchar(50)        declare @num varchar;        declare y_curr cursor for select b_id from [dbo].[mps_bookPlan]         open y_curr         fetch next from y_curr into @orderN         while(@@fetch_status=0)begin        select @num=count(c_id) from mps_comment where c_bid=@orderN        update mps_bookPlan set b_cnum=@num where b_id=@orderN        fetch next from y_curr into @orderN        end        close y_curr        deallocate y_curr