Horton

Re: So, is COUNT(*) fast now?

Tom Lane <tgl@sss.pgh.pa.us>

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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Robert Haas <robertmhaas@gmail.com>
Cc: Kevin Grittner <Kevin.Grittner@wicourts.gov>, pgsql-hackers@postgresql.org
Date: 2011-10-28T18:48:54Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. Remove pg_upgrade dependency on the 'postgres' database existing in the

Robert Haas <robertmhaas@gmail.com> writes:
> I also tried changing the BufferIsValid() tests in
> visibilitymap_test() to use BufferIsInvalid() instead, with the sense
> of the tests reversed (see attached vismap-test-invalid.patch).  Since
> BufferIsInvalid() just checks for InvalidBuffer instead of also doing
> the sanity checks, it's significantly cheaper.  This also reduced the
> time to about 330 ms, so seems clearly worth doing.

Hmm.  I wonder whether it wouldn't be better to get rid of the range
checks in BufferIsValid, or better convert them into Asserts.  It seems
less than intuitive that BufferIsValid and BufferIsInvalid aren't simple
inverses.

			regards, tom lane