Date compare in scheduling emplooyee job

Hi, I don't see how do you have this problem, I asume that you have 2 entities, workers and Jobs, the relation is several to several. So it gives birth to a new entity, jobs_x_workers; the fields of this new table are job_id, worker_id, (this two combined are usually the primary key, but you should add an jxw_id just in case the jobs where to be repeated), start_date and end_day. Since the record will be alway different, it can't fail. You shouldn't have warnings. What's the current structure of your DB??