-- SORT_QUERY_RESULTS explain SELECT * FROM ( SELECT 1 AS id FROM (SELECT * FROM src LIMIT 1) s1 UNION ALL SELECT 2 AS id FROM (SELECT * FROM src LIMIT 1) s1 UNION ALL SELECT 3 AS id FROM (SELECT * FROM src LIMIT 1) s2 UNION ALL SELECT 4 AS id FROM (SELECT * FROM src LIMIT 1) s2 CLUSTER BY id ) a; CREATE TABLE union_out (id int); insert overwrite table union_out SELECT * FROM ( SELECT 1 AS id FROM (SELECT * FROM src LIMIT 1) s1 UNION ALL SELECT 2 AS id FROM (SELECT * FROM src LIMIT 1) s1 UNION ALL SELECT 3 AS id FROM (SELECT * FROM src LIMIT 1) s2 UNION ALL SELECT 4 AS id FROM (SELECT * FROM src LIMIT 1) s2 CLUSTER BY id ) a; select * from union_out;