Well, it seems that Lucas took the day to bring simple and genial SQL
tricks.

But I think that you will need the 'day' factor, since you are taking 'day'
as a variable.

Maybe it's better for you to use TIMESTAMP fields anyway, do the operations
(it will take in account the midnight factor), and disregard the date
portion in the client.

This way your clients can pick up the limousine for any time, and your
software will work even if Bill Gates went to town for a week.

Artur