Skip site navigation (1) Skip section navigation (2)

Re: wip: functions median and percentile

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: David Fetter <david(at)fetter(dot)org>
Cc: Kevin Grittner <Kevin(dot)Grittner(at)wicourts(dot)gov>, Robert Haas <robertmhaas(at)gmail(dot)com>, Pavel Stehule <pavel(dot)stehule(at)gmail(dot)com>, Greg Stark <gsstark(at)mit(dot)edu>, PostgreSQL Hackers <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: wip: functions median and percentile
Date: 2010-08-19 17:25:36
Message-ID: 21527.1282238736@sss.pgh.pa.us (view raw or flat)
Thread:
Lists: pgsql-hackerspgsql-rrreviewers
David Fetter <david(at)fetter(dot)org> writes:
> On Thu, Aug 19, 2010 at 12:12:12PM -0500, Kevin Grittner wrote:
>> http://www.merriam-webster.com/dictionary/median
>> 
>> If you do a google search for "median" and poke around, you'll find
>> many places where this is the only definition mentioned; the others
>> seem to be rather infrequently used.  Why not make the commone usage
>> convenient?

> The reason not to is the same reason that MEDIAN doesn't appear in the
> SQL standard, namely that what's common in one field is wrong in
> another.

Hmm, do you have any *evidence* that that's why it's not in the standard?

My own take on that is that it's reasonably probable that the SQL
committee might standardize a function by that name someday.  What we
need to be worrying about is the prospect that if there are multiple
definitions for the term, they might pick a different one than we did.
A name like "arithmetic_median" seems much less likely to get blindsided
by future standardization.

			regards, tom lane

In response to

Responses

pgsql-hackers by date

Next:From: Heikki LinnakangasDate: 2010-08-19 17:36:09
Subject: Re: CommitFest 2009-07: Yay, Kevin! Thanks, reviewers!
Previous:From: Tom LaneDate: 2010-08-19 17:18:57
Subject: Re: CommitFest 2009-07: Yay, Kevin! Thanks, reviewers!

pgsql-rrreviewers by date

Next:From: Pavel StehuleDate: 2010-08-19 17:38:14
Subject: Re: wip: functions median and percentile
Previous:From: David FetterDate: 2010-08-19 17:14:58
Subject: Re: wip: functions median and percentile

Privacy Policy | About PostgreSQL
Copyright © 1996-2014 The PostgreSQL Global Development Group