Re: Converting row elements into a arrays? - Mailing list pgsql-general

From Rob Sargent
Subject Re: Converting row elements into a arrays?
Date
Msg-id e994b049-93f1-d739-e74c-ecd29bbbe4c5@gmail.com
Whole thread Raw
In response to Converting row elements into a arrays?  (Ron <ronljohnsonjr@gmail.com>)
Responses Re: Converting row elements into a arrays?  (Ron <ronljohnsonjr@gmail.com>)
List pgsql-general
On 3/2/23 13:58, Ron wrote:
> Postgresql 12.13
>
> Given the sample below, I'm looking for how to generate this output.  
> It's like GROUP BY, but generating an array instead of an aggreate 
> number.
>  f1 | f2_array
> ----+---------
> 1 | {1,2,3}
>   2 | {1,2,3,4}
>   3 | {1,2}
>
> The ultimate goal is to somehow use pg_index.indkey to get column 
> names from pg_attribute.
>
> create table foo (f1 int, f2 int);
> insert into foo values (1, 1);
> insert into foo values (1, 2);
> insert into foo values (1, 3);
> insert into foo values (2, 1);
> insert into foo values (2, 2);
> insert into foo values (2, 3);
> insert into foo values (2, 4);
> insert into foo values (3, 1);
> insert into foo values (3, 2);
>
> select * from foo order by f1, f2;
>  f1 | f2
> ----+----
>   1 |  1
>   1 |  2
>   1 |  3
>   2 |  1
>   2 |  2
>   2 |  3
>   2 |  4
>   3 |  1
>   3 |  2
> (9 rows)
>

In which environment are you accessing that array?  psql only?

>
>




pgsql-general by date:

Previous
From: "David G. Johnston"
Date:
Subject: Re: Converting row elements into a arrays?
Next
From: Ron
Date:
Subject: Re: Converting row elements into a arrays?