41. 在 SQL 中,如何定義一個觸發器? (A) CREATE TRIGGER trigger_name ON table_name
BEFORE INSERT AS BEGIN ... END; (B) CREATE TRIGGER trigger_name ON table_name FOR
EACH ROW BEGIN ... END; (C) CREATE TRIGGER trigger_name ON table_name AFTER INSERT
AS BEGIN ... END; (D) CREATE TRIGGER trigger_name ON table_name FOR EACH
STATEMENT BEGIN ... END;。