Re: Index usage when bitwise operator is used

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Hi Tom,

do you think it would be a good idea to ask GIN index team to
implement an int-based bitmap set indexing operator for GIN/GiST based
indexes? Or there will be a possibility to somehow optimally index
arrays of enumerations to implement such bitmap structures in 8.3 or
later postgresql versions?

With best regards,

-- Valentine

On Sep 17, 3:37 pm, t...@xxxxxxxxxxxxx (Tom Lane) wrote:
> "Kevin Grittner" <Kevin.Gritt...@xxxxxxxxxxxx> writes:
> > On Mon, Sep 17, 2007 at  2:49 AM, in message
> > <1190015368.148293.56...@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>, valgog
> > <val...@xxxxxxxxx> wrote:=20
> >> Are you sure you understood what was the question?
>
> >> Is the TBL1.CATEGORY = TBL2.CATEGORY the same as TBL1.CATEGORY &
> >> TBL2.CATEGORY > 0?
> > Yes, given that he stipulated that one and only one bit would be set.
>
> Really?  In that case, isn't this bit-field just a bad implementation of
> an enum-style field?
>
>                         regards, tom lane
>
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