652ed1b477
ID Generators: - AUTO_INCREMENT for INTEGER columns - SERIAL / BIGSERIAL as syntactic sugar - gen_random_uuid() / uuid() for UUID v4 generation - nextval() / currval() for sequence support - snowflake_id(node_id) for distributed 64-bit IDs - RETURNING clause for INSERT Deficiency Fixes: - Comma join: FROM t1, t2 now works as implicit CROSS JOIN - DEFAULT in restoreSchema: defaults survive server restart - Duplicate column names: t.id instead of id in joins - Empty result sets: always send column metadata to client - GROUP BY non-agg columns: return first row value instead of empty - Aggregate column names: count(*) instead of count() Bug fix: PK uniqueness check now uses correct key format