Re: Find free appointments faster

[Peter Brawley]

> I add a second to a possible start (08:10:01)

Ill-advised. There's a widely used convention for handling time periods. Widely used because it works, and avoids complications like the one you introduce.

Logically a time period may be ...

- closed-closed: includes both start date and end date,

- closed-open: includes the start date, excludes the end date,

- open-closed: excludes the start date and includes the end date,

- open-open: excludes both start date and end date.

The near-universal business default is closed-open: if you book a hotel room for 22-24 May, the hotel will expect you to arrive in the afternoon of 22 May and leave in the morning of 24 May, having stayed the two days of the closed:closed period 22-23 May, or the closed:open period 22-24 May. Obviously a temporal database needs a consistent convention. The common convention is closed-open periods. Your queries will be easier to develop, debug, optimise and maintain if you follow it.