Message-ID: <4C2504A3.4090502@wp.pl>
Date: Fri, 25 Jun 2010 21:33:55 +0200
From: Ireneusz Pluta <ipluta@wp.pl>
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To: Lee Hachadoorian <lee.hachadoorian@gmail.com>
CC: pgsql-sql <pgsql-sql@postgresql.org>
Subject: Re: Average of Array?
References: <AANLkTimbLPhLW7DzeTugvwClKBX-UQhOrUlR8afHydGB@mail.gmail.com>
In-Reply-To: <AANLkTimbLPhLW7DzeTugvwClKBX-UQhOrUlR8afHydGB@mail.gmail.com>
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Lee Hachadoorian pisze:
> Is there a function that returns the average of the elements of an
> array? I'm thinking of something that would work like the avg()
> aggregate function where it returns the average of all non-NULL
> values. Can't find anything like it in the docs, and I'd like to make
> sure I'm not missing something.
>
> Thanks,
>
>   
Use unnest() -> 
http://www.postgresql.org/docs/8.4/interactive/functions-array.html

# select avg(unnest) from (select unnest(ARRAY[1,2,null,3])) a;
        avg        
--------------------
 2.0000000000000000
(1 row)