On 02/03/2023 20:58, 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}
Something like this (off the top of my head)? -
select f1, array_agg(f2) as f2_array group by f1;
Hope that helps (and that it's right!).
Ray.
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)
--
Raymond O'Donnell // Galway // Ireland
r...@rodonnell.ie
