Postgres 12

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CREATE TABLE matrices (
id serial,
matrix text[][] NOT NULL
);

CREATE TABLE


INSERT INTO matrices(matrix) VALUES
(array[['1','2','3'],
       ['4','5','6']]),
(array[['f','e','d'],
       ['c','b','a']]);

INSERT 0 2


select * from matrices


id
matrix


1
{{1,2,3},{4,5,6}}

2
{{f,e,d},{c,b,a}}



SELECT 2


select id, array_agg(ar order by j) new_matrix
from (
	select m.id, j, array_agg(matrix[i][j] order by i) ar
	from matrices m
	cross join lateral generate_subscripts(m.matrix, 1) as s1(i)
	cross join lateral generate_subscripts(m.matrix, 2) as s2(j)
	group by m.id, j
) t
group by id


id
new_matrix


1
{{1,4},{2,5},{3,6}}

2
{{f,c},{e,b},{d,a}}



SELECT 2