本题考察两个知识点:
1、排序 order by 列名 (默认升序,+desc 降序)
2、在字符串里截取字符
left(字符串,位数) 从左截取几位
right(字符串,位数)从右截取几位
substring(字符串,第几位,位数) 从第几位开始截取,截取几位
select first_name from employees order by right(first_name,2);
select first_name from employees order by right(first_name,2);