Message-ID: <c5b36c72-ae87-4623-85a5-b487090923b4@gmail.com>
Date: Tue, 10 Mar 2026 19:53:30 +0100
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Subject: =?UTF-8?Q?Re=3A_LISTAGG_=C3=A0_la_Oracle_in_PostgreSQL?=
To: Paul A Jungwirth <pj@illuminatedcomputing.com>
Cc: "pgsql-general@lists.postgresql.org" <pgsql-general@lists.postgresql.org>
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 <CA+renyUW6+JUM5d6OJ8XZR3araY2iii5xTYP5kSUjqgLdY+uSg@mail.gmail.com>
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From: Pierre Forstmann <pierre.forstmann@gmail.com>
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I agree but I just would like to know if there is way to be compatible 
with Oracle syntax using aggregate features in PostgreSQL

Thanks.

Le 09/03/2026 à 23:05, Paul A Jungwirth a écrit :
> On Mon, Mar 9, 2026 at 1:21 PM Pierre Forstmann
> <pierre.forstmann@gmail.com> wrote:
>> Hello,
>>
>> I can write a LISTAGG aggregate for:
>>
>> create table emp(deptno numeric, ename text);
>>
>> SELECT deptno, LISTAGG(ename, ','::text ORDER BY ename) AS employees
>> FROM   emp GROUP BY deptno ORDER BY deptno;
>>
>> I would like to know if is possible to create an aggregate LISTAGG that
>> would work like in Oracle:
>>
>> SELECT deptno,
>>          listagg(ename, ',') WITHIN GROUP (ORDER BY ename) AS employees
>> FROM emp
>> GROUP BY deptno
>> ORDER BY deptno;
> I don't think you need a custom aggregate here. In Postgres you can say:
>
> select deptno,
>        string_agg(ename, ',' ORDER BY ename) AS employees
> FROM emp
> GROUP BY deptno
> ORDER BY deptno;
>