In a PHP application i am developing, I would like to know which way of the following is a good approach to create a meeting based on availability.
Option 1 - I am planing to keep predefined types of time slots such as, 8:00 am to 9:00 am (SLOT 1), 9:00 am to 10.00 am (SLOT 2) and etc. in a separate table called meeting_intervals
Option 2 - Letting a user to provide a FROM and TO time. i.e From 8:00 am to 9:30 pm. i feel this way its much more flexible.
Which of this can be useful in the long term plan ?