Re: distinct on extract returns composite type

Félix GERZAGUET <[email protected]> Sun, 29 Sep 2019 12:34:30 +0200

Newsgroups	gmane.comp.db.postgresql.performance
Message-ID	<CANVwZtuzT1w0aVQMyBi+U=d7e_HQmB70THnqZoxu=xooVRvhbA@mail.gmail.com>

Hello,

On Sun, Sep 29, 2019 at 11:46 AM Mariel Cherkassky <
[email protected]> wrote:

> I'm keep getting composite type (row) instead of two columns. Is there any
> sql way to convert the row type into two columns ? I want to get the first
> and last dates of each quarter with those columns and with this composite
> type I failed doing it
>

This seems to work as you expect:

select distinct extract(year from end_time) as year, extract(quarter from
end_time) quarter from generate_series
        ( '2017-09-01'::timestamp
        , '2019-04-01'::timestamp
        , '3 month'::interval) end_time
;

https://www.postgresql.org/docs/current/sql-select.html#SQL-DISTINCT

--

Félix