Re: AGREGATE FUNCTIONS

Started by Heikki Linnakangasover 19 years ago2 messages
#1Heikki Linnakangas
hlinnaka@iki.fi

On Tue, 6 Jun 2006, Roberto Rezende de Assis wrote:

Hello, I would like to know where in the source-code of postgres is located
the code of the aggregate functions min, max, avg.

They're in src/backend/utils/adt/numeric.c

I wish to develop more statistical aggregate functions, and I prefer to use C
than to write then in the PL/R.

Make sure you read section "32.10 User-Defined aggregates" in the manual:

http://www.postgresql.org/docs/current/interactive/xaggr.html

Also, take a look at contrib/intagg for another example.

- Heikki

#2Joshua D. Drake
jd@commandprompt.com
In reply to: Heikki Linnakangas (#1)

Roberto Rezende de Assis wrote:

Hello, I would like to know where in the source-code of postgres is
located the code of the aggregate functions min, max, avg.
I wish to develop more statistical aggregate functions, and I prefer to
use C than to write then in the PL/R.

http://projects.commandprompt.com/public/pgsql/browser/trunk/pgsql/src/backend/utils/adt
http://projects.commandprompt.com/public/pgsql/browser/trunk/pgsql/src/backend/utils/adt/numeric.c
http://projects.commandprompt.com/public/pgsql/browser/trunk/pgsql/src/backend/utils/adt

That will give you and easy interface to view the code and everything
after browser is the CVS source tree so you can look for yourself within
your copy of HEAD or 8.1 or whatever.

Sincerely,

Joshua D. Drake

Thanks

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