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Re: Feature request for count_estimate(samplesize) aggregate or SAMPLE keyword

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I am not aware of this, sounds like what I want. Will look into it. Thanks!

Am 01.09.22 um 03:47 schrieb Tom Lane:
Torge <torgato@xxxxxxxxx> writes:
Now I would like to humbly propose a feature that gives an easy way to
get a quick count estimate for any condition - index based or not -
based on a random sample of rows, that does not require a custom
function creation or complex SQL statement
Can't you do that already using TABLESAMPLE?  For example, to
use a 1% sample:

select count(*) * 100 from mytab tablesample system(1) where <condition>;

You do have to remember to multiply by the factor corresponding
to your sample rate, but aside from that annoyance this (a)
already exists, (b) is SQL-standard, and (c) can be adapted to
a lot of other kinds of analysis besides plain count(*).

			regards, tom lane






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