DELETE FROM courses WHERE course_designater = 'Java110';
DELETE FROM classconvenings
WHERE classes_num_fk > 4
AND class_convene_date = TO_DATE('2006-02-15 00:00:00','YYYY-MM-DD HH24:MI:SS')
AND class_location_fk = 'Seattle-Training Room 1';
-- 建表、插入 8 筆測試數據
DELETE FROM employee WHERE salary > 3000; -- 刪除 4 筆
SELECT * FROM employee; -- 剩餘 4 筆低薪記錄
DELETE FROM project WHERE pro_id = 1006; -- 0 rows deleted
注意：DELETE 需 COMMIT 生效，ROLLBACK 可撤銷；大量刪除建議分批提交避免回滾段膨脹。
