Re: using index on comparison with bit-operation?

Bruno Wolff III wrote:
> On Wed, Apr 07, 2004 at 06:01:03 -0700,
>   Michael Groth <geek_1981@yahoo.de> wrote:
> > hi,
> > 
> > is it possible to use an index on the expression '(table_1.field &
> > table_2.field)::int > 0' ?
> > 
> > here's the whole query:
> > 
> > SELECT 
> >     COUNT(*)
> > FROM
> >     users AS users
> > JOIN
> >     search_profile AS search_profile ON
> > (search_profile.bin_matching_field_0 &
> > users.bin_matching_field_0)::int > 0
> > WHERE
> >     users.id = 190
> 
> In 7.4 you can create indexes on expressions.

But it uses two different tables.  You can't mix tables in an index, can
you?

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