$$ Validate each field again on the server side to prevent tampering with client$-$side

validation.

$$ Sanitize and validate user inputs to prevent SQL injection and other attacks $($you are

free to use and enforce any validation you want $($THIS IS YOUR SYSTEM, YOU ARE A

DEVELOPER$).$

$$ Ensure that the appointment date and time are available $($not already booked by

another patient$).$

$$ Handle any errors that occur on the server side gracefully and provide informative

messages to the user.