1、题目描述:
查找当前薪水(to_date=‘9999-01-01‘)排名第二多的员工编号emp_no、薪水salary、last_name以及first_name,不准使用order by
CREATE TABLE `employees` (
`emp_no` int(11) NOT NULL,
`birth_date` date NOT NULL,
`first_name` varchar(14) NOT NULL,
`last_name` varchar(16) NOT NULL,
`gender` char(1) NOT NULL,
`hire_date` date NOT NULL,
PRIMARY KEY (`emp_no`));
CREATE TABLE `salaries` (
`emp_no` int(11) NOT NULL,
`salary` int(11) NOT NULL,
`from_date` date NOT NULL,
`to_date` date NOT NULL,
PRIMARY KEY (`emp_no`,`from_date`));
输入描述:
无
输出描述:
emp_no | salary | last_name | first_name |
---|---|---|---|
10009 | 94409 | Peac | Sumant |
2、代码:
(1)解法1:除了最高工资就是它最高,先找到最高工资,然后找到第二高工资
select e.emp_no,max(s.salary),e.last_name,e.first_name from employees e, salaries s where s.salary < (select max(salary) from salaries) and s.to_date="9999-01-01" and e.emp_no=s.emp_no;
(2)解法2:表内连接求第二高工资
select e.emp_no,s.salary,e.last_name,e.first_name from employees e join salaries s on e.emp_no=s.emp_no where s.to_date=‘9999-01-01‘ and s.salary = ( select s1.salary from salaries s1 join salaries s2 on s1.salary<=s2.salary where s1.to_date=‘9999-01-01‘ and s2.to_date=‘9999-01-01‘ group by s1.salary having count(distinct s2.salary)=2 );
原文地址:https://www.cnblogs.com/guoyu1/p/12242344.html
时间: 2024-11-06 15:11:07