SET allow_experimental_analyzer = 0; DROP TABLE IF EXISTS test_table; CREATE TABLE test_table ( id UInt64, value String ) ENGINE=TinyLog; INSERT INTO test_table VALUES (0, 'Value'); -- { echoOn } SELECT 'Union constants'; SELECT 1 UNION ALL SELECT 1; SELECT '--'; SELECT 1 UNION DISTINCT SELECT 1 UNION ALL SELECT 1; SELECT '--'; SELECT 1 INTERSECT SELECT 1; SELECT '--'; SELECT 1 EXCEPT SELECT 1; SELECT '--'; SELECT id FROM (SELECT 1 AS id UNION ALL SELECT 1); SELECT 'Union non constants'; SELECT value FROM (SELECT 1 as value UNION ALL SELECT 1 UNION ALL SELECT 1); SELECT '--'; SELECT id FROM test_table UNION ALL SELECT id FROM test_table; SELECT '--'; SELECT id FROM test_table UNION DISTINCT SELECT id FROM test_table; SELECT '--'; SELECT id FROM test_table INTERSECT SELECT id FROM test_table; SELECT '--'; SELECT id FROM test_table EXCEPT SELECT id FROM test_table; SELECT '--'; SELECT id FROM (SELECT id FROM test_table UNION ALL SELECT id FROM test_table); SELECT '--'; SELECT id FROM (SELECT id FROM test_table UNION DISTINCT SELECT id FROM test_table); SELECT '--'; SELECT id FROM (SELECT id FROM test_table INTERSECT SELECT id FROM test_table); SELECT '--'; SELECT id FROM (SELECT id FROM test_table EXCEPT SELECT id FROM test_table); -- { echoOff } DROP TABLE test_table;