• 2022-06-15
    下面的代码用于创建一个在删除数据前触发的触发器,横线上所缺代码为( )。 DELIMITER // CREATE DEFINER=`root`@`localhost` TRIGGER ____________________ ON tb_bookinfo FOR EACH ROW INSERT INTO tb_booklog (event,logtime) values('删除了一条图书信息',now());
    A: BEFORE DELETE
    B: AFTER DELETE
    C: BEFORE INSERT
    D: AFTER INSERT