Re: avg() from multiple columns

If you want row by row averages try this:

select (col1+col2+col3)/3 from table;

If you wnat to average several columns over the whole table this seems to
work:

select avg(col1+col2+col3) from table;

Regards
Jason

On Sun, 2 Sep 2001, Miia Uski wrote:

> I have a question regarding taking the average value from several
> columns.
>
> I am trying to evaluate a survey with sql. I have one column per
> question, and one row per answered survey. The answers can have values 1
>
> - 4, unanswered questions have 0. I want to take the average from the
> answers of several questions that belong to the same category. For one
> question I can do like this:
>
> igv=> select avg("1.2") from igvdata
> igv-> where "1.2" > 0;
>
> How do I go about to have averages for several columns? Do I have to
> create views in order to avoid the "no answer"-values for each column?
>
>
> Thanks in advance,
>
> Miia
>
>
>
>
> ---------------------------(end of broadcast)---------------------------
> TIP 1: subscribe and unsubscribe commands go to majordomo@postgresql.org
>

--
------------------------------------------------------------------------------
Jason Tan                                                jason@rebel.net.au
     "Democracy is two wolves and a lamb voting on what to have for lunch.
                 Liberty is a well-armed lamb contesting the vote."
                               ~Benjamin Franklin, 1759
------------------------------------------------------------------------------