Thread: Extracting data from arrays
Hi all,
I've this query including arrays:
SELECT hour[1:5], statistics_date FROM statistics_dailyWHERE 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!
--
Dani Castaños Sánchez
dcastanos@androme.es
Hello
postgres=# create or replace function sum_items(bigint[]) returns
bigint as $$ select sum($1[i])::bigint from
generate_series(array_lower($1,1), array_upper($1,1)) g(i)$$ language
sql immutable;
CREATE FUNCTION
Time: 2,510 ms
postgres=# select sum_items(array[1,2,3,4]); sum_items
----------- 10
(1 row)
regards
Pavel Stehule
2009/5/18 Dani Castaños <dcastanos@androme.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!
>
> --
> Dani Castaños Sánchez
> dcastanos@androme.es
>
>
>
> --
> Sent via pgsql-sql mailing list (pgsql-sql@postgresql.org)
> To make changes to your subscription:
> http://www.postgresql.org/mailpref/pgsql-sql
>
In article <162867790905180410n670062b0ud2d7fdd0e6521a2@mail.gmail.com>,
Pavel Stehule <pavel.stehule@gmail.com> writes:
> Hello
> postgres=# create or replace function sum_items(bigint[]) returns
> bigint as $$ select sum($1[i])::bigint from
> generate_series(array_lower($1,1), array_upper($1,1)) g(i)$$ language
> sql immutable;
> CREATE FUNCTION
> Time: 2,510 ms
> postgres=# select sum_items(array[1,2,3,4]); sum_items
> -----------
> 10
> (1 row)
> regards
> Pavel Stehule
> 2009/5/18 Dani Castaños <dcastanos@androme.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.
FWIW, in PostgreSQL 8.4 you won't need your own sum_items function any
more:
SELECT sum(unnest), statistics_date
FROM ( SELECT statistics_date, unnest(hour) FROM t1 ) AS dummy
WHERE statistics_date = '2008-01-03'
GROUP BY statistics_date
Thank you very much!
-----Mensaje original-----
De: Pavel Stehule [mailto:pavel.stehule@gmail.com]
postgres=# create or replace function sum_items(bigint[]) returns
bigint as $$ select sum($1[i])::bigint from
generate_series(array_lower($1,1), array_upper($1,1)) g(i)$$ language
sql immutable;
CREATE FUNCTION
Time: 2,510 ms
postgres=# select sum_items(array[1,2,3,4]); sum_items
----------- 10
(1 row)
regards
Pavel Stehule
2009/5/18 Dani Castaños <dcastanos@androme.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!
>
> --
> Dani Castaños Sánchez
> dcastanos@androme.es
>
>
>
> --
> Sent via pgsql-sql mailing list (pgsql-sql@postgresql.org)
> To make changes to your subscription:
> http://www.postgresql.org/mailpref/pgsql-sql
>