delimiter // # 修改mysql的终止符，把原来的；改为//
NEW 新数据 OLD 老数据
插入前
CTREATE TRIGGER 名字 BEFORE INSERT ON 表名 FOR EACH ROW
BEGIN
insert into tb2(...)
END
插入后
CTREATE TRIGGER 名字 AFTER INSERT ON 表名 FOR EACH ROW
BEGIN
insert into tb2(...)
END
删除前
CTREATE TRIGGER 名字 BEFORE DELETE ON 表名 FOR EACH ROW
BEGIN
insert into tb2(...)
END
删除后
CTREATE TRIGGER 名字 AFTER DELETE ON 表名 FOR EACH ROW
BEGIN
insert into tb2(...)
END
更新前
更新后