I am trying to find a way to prevent double booking.
In my booking form, i have date(date/time),start time(date/time) and doctor ID(number)-all from tblBooking
For example, doctor 1 9/6/2016 9:00. then next time i enter this information into form which should prevent me doing this and an error message should display.
What code should i put into this form? (code for multiple fields)