Mysql触发器

create trigger tapp_trigger after update
on business FOR EACH ROW
begin  
set @count = (select count(*) from temp where business_id = old.id);
set @Differ = (SELECT sum(TIMESTAMPDIFF(minute , create_time, modify_time)) from business where id = old.id );
if @count = 0 then  
	insert into temp(business_id, start_time, differ) values(old.id, old.create_time, @Differ);
elseif @count > 0 THEN
	update temp set differ=@Differ where business_id = old.id;
end if;  
end;