-- Q18: Large Volume Customer
-- Operators: 3-table Join -> IN subquery with HAVING -> Aggregate
-- TopK: ORDER BY + LIMIT restored (now supported by pg_trickle)
SELECT
    c_name,
    c_custkey,
    o_orderkey,
    o_orderdate,
    o_totalprice,
    SUM(l_quantity) AS total_qty
FROM customer, orders, lineitem
WHERE o_orderkey IN (
    SELECT l_orderkey
    FROM lineitem
    GROUP BY l_orderkey
    HAVING SUM(l_quantity) > 300
)
  AND c_custkey = o_custkey
  AND o_orderkey = l_orderkey
GROUP BY c_name, c_custkey, o_orderkey, o_orderdate, o_totalprice
ORDER BY o_totalprice DESC, o_orderdate
LIMIT 100