Re: wip: functions median and percentile
David Fetter <david@fetter.org>
From: David Fetter <david@fetter.org>
To: Kevin Grittner <Kevin.Grittner@wicourts.gov>
Cc: Robert Haas <robertmhaas@gmail.com>, Pavel Stehule <pavel.stehule@gmail.com>, Greg Stark <gsstark@mit.edu>, PostgreSQL Hackers <pgsql-hackers@postgresql.org>, Tom Lane <tgl@sss.pgh.pa.us>
Date: 2010-08-19T17:14:58Z
Lists: pgsql-hackers
On Thu, Aug 19, 2010 at 12:12:12PM -0500, Kevin Grittner wrote: > David Fetter <david@fetter.org> wrote: > > > Median may be useful, but we pretty much can't just call it > > "median." Instead, we need to call it something like "left_median" > > or "arithmetic_median." > > I think it would be reasonable, and perhaps preferable, to use just > "median" for the semantics described in most dictionaries -- for > example, this: > > 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. Cheers, David. -- David Fetter <david@fetter.org> http://fetter.org/ Phone: +1 415 235 3778 AIM: dfetter666 Yahoo!: dfetter Skype: davidfetter XMPP: david.fetter@gmail.com iCal: webcal://www.tripit.com/feed/ical/people/david74/tripit.ics Remember to vote! Consider donating to Postgres: http://www.postgresql.org/about/donate