select name "n", age "a", sex "s", height "h" from person; (带上""双引号显示的和双引号里面的一样)select name n, age a, sex s, height h from person;(不带""双引号显示的是n、a、s、h的大写)select name as "名字", age as "年龄", sex as "性别", height as "身高" from person;(as可要可不要)