SQL Trivia

SELECT, WHERE, ORDER BY, LIMIT, DISTINCT — the everyday core.

INNER, LEFT, RIGHT, FULL, CROSS, self-joins, and the canonical patterns.

COUNT, SUM, AVG, HAVING, conditional aggregation.

RANK, ROW_NUMBER, LAG/LEAD, running totals, partitioning.

Inline subqueries, correlated subqueries, WITH clauses.

EXPLAIN plans, indexes, query optimisation.

TEXT vs INTEGER, dates, timestamps, casting.

Three-valued logic, IS NULL, COALESCE, NULL in aggregates.