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From: Tom Lane <[email protected]>
To: Robert Haas <[email protected]>
Cc: Ilia Evdokimov <[email protected]>
Cc: Matthias van de Meent <[email protected]>
Cc: Andrei Lepikhov <[email protected]>
Cc: [email protected]
Cc: Guillaume Lelarge <[email protected]>
Cc: Matheus Alcantara <[email protected]>
Cc: Alena Rybakina <[email protected]>
Subject: Re: explain analyze rows=%.0f
Date: Mon, 31 Mar 2025 13:49:55 -0400
Message-ID: <[email protected]> (raw)
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Robert Haas <[email protected]> writes:
> But why isn't it just as valuable to have two decimal places for the
> estimate? I theorize that the cases that are really a problem here are
> those where the row count estimate is between 0 and 1 per row, and
> rounding to an integer loses all precision.

Currently, the planner rounds *all* rowcount estimates to integers
(cf. clamp_row_est()).  Maybe it'd be appropriate to rethink that,
but it's not just a matter of changing EXPLAIN's print format.

			regards, tom lane

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