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help / color / mirror / Atom feedFrom: Tom Lane <[email protected]>
To: Stephen Samuel (Sam) <[email protected]>
Cc: Peter Geoghegan <[email protected]>
Cc: [email protected]
Subject: Re: Trying to understand why a query is filtering when there is a composite index
Date: Mon, 19 Aug 2024 19:55:26 -0400
Message-ID: <[email protected]> (raw)
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"Stephen Samuel (Sam)" <[email protected]> writes:
> This index covers both columns needed in the predicate/projection, and the
> visibility bit is almost always set, why does it need to go to the heap at
> all and doesn't just get what it needs from the index?
Peter's theory was that the particular tuples you were fetching were
in not-all-visible pages. That seems plausible to me.
regards, tom lane
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