Re: FIRST_VALUE argument must appear in group by?

On Tue, May 17, 2016 at 12:04 AM, Guyren Howe <guyren(at)gmail(dot)com> wrote:

> On May 16, 2016, at 20:48 , David G. Johnston <david(dot)g(dot)johnston(at)gmail(dot)com>
> wrote:
>
>
> On Monday, May 16, 2016, Guyren Howe <guyren(at)gmail(dot)com> wrote:
>
>> I have this SELECT clause as part of a larger query:
>>
>> FIRST_VALUE(drs.id) OVER (PARTITION BY drs.order_ID ORDER BY drs.position ASC) AS current_drs_id
>>
>> Seems reasonable to me: group and sort the fields in this table and give
>> me the first value.
>>
>> But I get "column "drs.id" must appear in the GROUP BY clause or be used
>> in an aggregate function".
>>
>> Huh?
>>
>
> The larger query would help…
>
>
> SELECT
> o.id,
> os.status AS status,
> o.status_updated_at,
> o.should_hold_at_airlines,
> (SELECT drs2.id FROM delivery_route_segments drs2 WHERE drs2.order_id = o.id AND NOT drs2.completed ORDER BY drs2.position LIMIT 1) AS current_drs_id,
>
>
> FROM
> orders o JOIN
> order_statuses os ON (o.status = os.id) JOIN
> delivery_route_segments drs ON (drs.order_id = o.id) JOIN
> pick_up_addresses pua ON (pua.order_id = o.id)
> GROUP BY
> o.id, os.status
>
> I would prefer to do the subquery as a window function, both because that
> is cleaner to read and also because I believe it is likely to be more
> efficient.
>
>
​This query is non-functional. It has a GROUP BY without any aggregate
functions and not all of the selected columns are in the group by.

David J.