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From: Tom Lane <tgl@sss.pgh.pa.us>
To: steven.winfield@cantabcapital.com
cc: pgsql-docs@postgresql.org
Subject: Re: Median missing from aggregate functions page
In-reply-to: <20161223102056.25614.1166@wrigleys.postgresql.org>
References: <20161223102056.25614.1166@wrigleys.postgresql.org>
Comments: In-reply-to steven.winfield@cantabcapital.com
	message dated "Fri, 23 Dec 2016 10:20:56 +0000"
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Date: Fri, 23 Dec 2016 10:21:39 -0500
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steven.winfield@cantabcapital.com writes:
> The index contains an entry for &quot;median&quot; on the aggregate funct=
ions page,
> but there is no mention of it there.

Hm --- that <indexterm> entry is attached to the percentile_cont()
function, which can be used to implement median, but I agree that
a person who already knew that would probably not be following the
index pointer.

It might be more useful to point to 4.2.7. Aggregate Expressions
which contains a concrete example of how to implement median
with percentile_disc().

Another idea is to just make the index entry say
"See percentile_cont() and percentile_disc()".

			regards, tom lane


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