Write a migration and ActiveRecord model that tracks restaurant reservations. Assume there is a table in your relational database named “reservations”. Reservations have a start time, an end time and a table number.

Write some ActiveRecord validations that check new reservations for overbooking of the same table in the restaurant. For example, table #10 cannot have 2 reservations for the same period of time. This validation(s) should check time overlap for both record creation and updates.

Unit tests are a must to make sure your double booking validations are working. (rspec and unittests)