SELECT·INSERT·UPDATE·DELETE
ROLLBACK ✅·명시 COMMIT·WHERE ✅·행 단위
SELECT·FROM·WHERE·GROUP BY·HAVING·ORDER BY
처리(실행) 순서 — FROM부터
비교·논리·BETWEEN·IN·LIKE·IS NULL
COUNT·SUM·AVG·MAX·MIN
INNER·LEFT·RIGHT·FULL·CROSS
DELETE vs TRUNCATE vs DROP
σ·π·⋈·÷ ↔ WHERE·SELECT·JOIN·HAVING