SELECT range(x) AS k, count() FROM (SELECT number % 2 ? number : 0 AS x FROM system.numbers LIMIT 10) GROUP BY k ORDER BY k;
SELECT range(x) AS k1, range(y) AS k2, count() FROM (SELECT number % 2 ? number : 0 AS x, number % 3 ? toUInt64(20 - number) : 0 AS y FROM system.numbers LIMIT 20) GROUP BY k1, k2 ORDER BY k1, k2;