1、入职时间倒叙排列

select hire_date from employees order by hire_date desc

2、入职时间倒数第三的时间

select hire_date from employees order by hire_date desc limit 1 offset 2

3、入职时间倒数第三的员工信息

select * from employees where hire_date = (select hire_date from employees order by hire_date desc limit 1 offset 2)