-- UNION
(SELECT s FROM t1) UNION (SELECT s FROM t2);

(SELECT s FROM t1) UNION ALL (SELECT s FROM t2);

-- INTERSECT
(SELECT s FROM t1) INTERSECT (SELECT s FROM t2);

(SELECT s FROM t1) INTERSECT ALL (SELECT s FROM t2);

-- EXPECT
(SELECT s FROM t1) EXCEPT (SELECT s FROM t2);

(SELECT s FROM t1) EXCEPT ALL (SELECT s FROM t2);

-- IN
SELECT user, amount
FROM Orders
WHERE product IN (
    SELECT product FROM NewProducts
)

-- EXISTS
SELECT user, amount
FROM Orders
WHERE product EXISTS (
    SELECT product FROM NewProducts
)