Re: Can Postgres use an INDEX over an OR?

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От Tom Lane
Тема Re: Can Postgres use an INDEX over an OR?
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Msg-id 10074.1248704308@sss.pgh.pa.us
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Ответ на Re: Can Postgres use an INDEX over an OR?  (Віталій Тимчишин <tivv00@gmail.com>)
Ответы Re: Can Postgres use an INDEX over an OR?  (Віталій Тимчишин <tivv00@gmail.com>)
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=?KOI8-U?B?96bUwcymyiD0yc3eydvJzg==?= <tivv00@gmail.com> writes:
> Actually what I am talking about is to make OR with UNION (or UNION-like
> because it's a little different depending on input rows uniqueness) as an
> option. All of OR parts can use/not use different strategies (including
> multiple different idexes or hash joins).

AFAICS you're proposing re-inventing the old implementation of OR'd
indexscans.  We took that out when we added bitmap scans because it
didn't have any performance advantage over BitmapOr.

            regards, tom lane

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