Why your query is slow

Every question bank you've used so far seeds a handful of rows — a query that scans the whole table finishes instantly whether it's smart or not. This warehouse is ~300,000 rides and ~300,000 payments, no indexes. At this size, a bad plan is visible: the same query that takes 1ms on 20 rows takes tens of milliseconds here, and the difference shows up in EXPLAIN ANALYZE, not just in a stopwatch.