Re: SUM Array values query

2009/5/18 Dani Castaños <dcastanos(at)androme(dot)es>:
> Hi all,
>
> I've this query including arrays:
>
> SELECT hour[1:5], statistics_date
>  FROM statistics_daily
>  WHERE statistics_date = to_date( '03/01/2008', 'DD/MM/YYYY' )
>
> Result:
>
>            hour            | statistics_date
> ----------------------------+-----------------
>  {1800,1800,1800,1800,1800} | 2008-01-03
>
>
> I'm just wondering if there's some way to retrieve the hour column as the
> sum of the array values... Just like this:
>
>            hour            | statistics_date
> ----------------------------+-----------------
>  9000                       | 2008-01-03
>
>
> Hour is a bigint[] array column.
> My version of postreSQL is 8.1.9
>
> Thank you in advanced!
>
> P.S.: Sorry if I had send it before, but I think I was not subscribed to the
> mailist.
>
> --
> Dani Castaños Sánchez
> dcastanos(at)androme(dot)es
>
>
>
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Create function in pure sql and ...

,-[15:27:18]merlin(at)[local]:5432=
`-merlin>create function array_sum (bigint[]) returns bigint as $$
SELECT sum($1[i])::bigint FROM
generate_series(array_lower($1,1),array_upper($1,1)
) index(i); $$ language sql;
CREATE FUNCTION
Time: 16,203 ms
,-[15:28:02]merlin(at)[local]:5432=
`-merlin>select array_sum(col_array) from t30;
array_sum
-----------
9000
(1 row)

:)

--
Pawel Socha
pawel(dot)socha(at)gmail(dot)com