Re: explain analyze rows=%.0f - Mailing list pgsql-hackers

From Tom Lane
Subject Re: explain analyze rows=%.0f
Date
Msg-id 4118244.1743443395@sss.pgh.pa.us
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In response to Re: explain analyze rows=%.0f  (Robert Haas <robertmhaas@gmail.com>)
Responses Re: explain analyze rows=%.0f
List pgsql-hackers
Robert Haas <robertmhaas@gmail.com> 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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