I have to work with a MS Access appointment table that only has records of booked appointments. There is an [Date] field for the date of the appointment, a [Time] field for the time of the appointment and a [Length] field for appointment length. So an appointment starts at [Date] + [Time] and ends at [Date] + [Time] + [Length].

If I want to find the next available 1 hour opening starting 24 hours from the present and on ward, I would need a way query the appointment table and check for any 1 hour or more "gaps" between consecutive records, assuming a table ordered by time.

What kind of sql string(s) would be need to accomplish this?

Thanks.