Hello Diaa.

Take into account how you want to make this filter, it may be that an appointment is a reservation 24 hours or for hours or for hours with minutes.

There is a lot of complexity.

In particular, I would record the time of the appointment in a table in the appointment registry.

and every time I have a new appointment, consult the DB by date to that table, if it does not return records, it would mean that I do not have an appointment.

I hope it helps you.

Greetings.