On Fri, 20 May 2011 11:37:36 -0500,
Jack Christensen <jackc(at)hylesanderson(dot)edu> wrote:
[...]
> In a similar project I worked on start time for a loan was always the
> current time so overlaps weren't an issue. I don't have any firsthand
> experience with them, but it sounds like what you want are exclusion
> constraints.
> http://www.depesz.com/index.php/2010/01/03/waiting-for-8-5-exclusion-constraints/
This lead to a more general solution presented nicely by Jeff Davis:
http://pgfoundry.org/projects/temporal
http://www.slideshare.net/pgconf/not-just-unique-exclusion-constraints
Cheers,
--
Seb