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Window functions, recursive CTEs, isolation levels, EXPLAIN/plans, upsert patterns, deadlocks, and advanced join/set techniques. Mix of single-answer and multiple-answer items.
LEFT/anti-joins, GROUP BY/HAVING, subqueries, CTEs, CASE/COALESCE, EXISTS, set ops nuance, and basic transaction/index awareness. Mix of single-answer and multiple-answer items.
Core SQL: SELECT, WHERE, ORDER BY, NULL, aggregates, DISTINCT, LIKE, and simple INNER JOIN. Mix of single-answer and multiple-answer items; multi-select questions ask you to select every correct statement.
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