Re: date overlap

[Quoted] In article <hJV%5.14235$bw.1170406_at_news.flash.net>,   "Eric Givler" <egivler_at_flash.net> wrote:
> What's the quickest/most efficient way to check for an overlapping
 date
> range in a SQL statement?
>
> Table A:
> blocked areas
> area_eid number
> start_date date
> end_date date
>
> Table B:
> Reservation
> Area_eid number
> arrival_date date
> departure_date date
>
> I don't want to allow reservations that have a "block" record in
 table A
> with an "overlap" of the date range. There are 7 different
 possibilities
> for the dates to fall into, 2 of which wouldn't be overlapping the
 block
> (the ones where both the start and ends appear before or after the
 block).
> How do I detect the rest EASILY?
>
> Thanks!
>
>

[Quoted] there are two ways

      arrival_date between start_date and end_date
      OR
      departure_date between start_date and end_date

Another:

     arrival_date <= end_date and
     departure_date >= start_date

--
[Quoted] Michael Krolewski
Rosetta Inpharmatics
mkrolewski_at_rii.com
              Usual disclaimers


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