多项选择题

A.select*from t1 where city_name="北京"orcity_name="上海";
B.select*from t1 where city_name="北京"and city_name="上海";
C.select*from t1 where city_name in("北京","上海");
D.select*from t1 where city_name in"北京"or"上海";