Hi, I have a Booking ID form which you enter in bookings made by customers. There are multiple Customer IDs which can make multiple Bookings (Booking IDs). They book certain Trips (Trip IDs) to go on.
What I'm trying to do, is make it so that I can only allocate 20 customers to a Trip ID and no more, and make an error message displayed if I try to add more than 20 customers to a Trip ID. I've searched google and can't work out a way of doing this.
Please message back if I need to add any further information.
What I'm trying to do, is make it so that I can only allocate 20 customers to a Trip ID and no more, and make an error message displayed if I try to add more than 20 customers to a Trip ID. I've searched google and can't work out a way of doing this.
Please message back if I need to add any further information.
