Postgres 10

By using db<>fiddle, you agree to license everything you submit by Creative Commons CC0.

CREATE TABLE tab(time INT, col INT[])

CREATE TABLE

INSERT INTO tab VALUES (1, '{1,2}'), (1, '{3,4,5,6}'), (2, '{}'), (2, '{7}'), (2, '{8,9,10}'), (3, '{11,12,13,14,15}')

INSERT 0 6

SELECT time, array_agg(elem order by nr)
FROM (SELECT time, nr, SUM(elem) AS elem
      FROM tab,unnest(col) WITH ORDINALITY a(elem, nr)
      GROUP BY time,nr) s
GROUP BY time

time
array_agg

1
{4,6,5,6}

2
{15,9,10}

3
{11,12,13,14,15}

SELECT 3

\

ERROR:  syntax error at or near "\"
LINE 1: \
        ^