On my current databse I am trying to develop a schedule system (drop down menu with start and finish times with dates) were the user is unable to double book a customer to hire a venue for an event. Is it possible based on times of a venue being booked at a specific time that if the user booked a time a pop-up message would appear and explain to them that the venue is currently booked at that location and will be available at another particular tims? Is this possible to perform with code? If so how can it be done? Do you have any good examples?



Thanks