Re: Efficient date range search?

On Mon, Oct 07, 2002 at 13:32:09 -0400,
  Jean-Luc Lachance <jllachan@nsd.ca> wrote:
> Alvaro Herrera wrote:
> >
> > On Mon, Oct 07, 2002 at 12:11:35PM -0400, Jean-Luc Lachance wrote:
> > > Shridhar Daithankar wrote:
> > > > Create an index on died field. And query like
> > > >
> > > > select * from pets where died < "last year july 4 7:01 PM;
> >
> > > If the pet is still alive today died would be NULL and the where clause
> > > would not be true.
> >
> > In that case check for NULL explicitly,
> >
> > select * from pets where died > [date] or died is null;
>
>
> Then you're back to whole table scan... :(

You could use 'infinity'::timestamp as a code for pets that are currently
alive instead of null.