-- { echoOn }

SELECT id, value_element, value FROM test_table ARRAY JOIN [[1,2,3]] AS value_element, value_element AS value;
0	[1,2,3]	[1,2,3]
SELECT id, value_element, value FROM test_table ARRAY JOIN [[1,2,3]] AS value_element ARRAY JOIN value_element AS value;
0	[1,2,3]	1
0	[1,2,3]	2
0	[1,2,3]	3
SELECT value_element, value FROM test_table ARRAY JOIN [1048577] AS value_element, arrayMap(x -> value_element, ['']) AS value;
1048577	[1048577]
SELECT arrayFilter(x -> notEmpty(concat(x)), [NULL, NULL]) FROM system.one ARRAY JOIN [1048577] AS elem, arrayMap(x -> concat(x, elem, ''), ['']) AS unused; -- { serverError 44 }