Sure, but then our database will be a bottleneck and we actually can just use SQL for everything and not to forward information to another storage (like Redis)

Sure, but then our database will be a bottleneck and we actually can just use SQL for everything and not to forward information to another storage (like Redis) since there are no benefits. If you will deploy live system several times a day, eventually you will lose some data. Also, implementing monitoring for this is not an easy task and you will probably will never know if job wasn't scheduled.