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

From Ron
Subject Converting row elements into a arrays?
Date
Msg-id 788ab733-d0d1-7791-fb22-7c2724b08816@gmail.com
Whole thread Raw
Responses Re: Converting row elements into a arrays?  (Ray O'Donnell <ray@rodonnell.ie>)
Re: Converting row elements into a arrays?  ("David G. Johnston" <david.g.johnston@gmail.com>)
Re: Converting row elements into a arrays?  (Rob Sargent <robjsargent@gmail.com>)
List pgsql-general
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)



-- 
Born in Arizona, moved to Babylonia.



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