2018年(273)
分类: Mysql/postgreSQL
2018-08-13 11:24:46
题目描述
查找最晚入职员工的所有信息
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`));
输入描述:
无
输出描述:
emp_no | birth_date | first_name | last_name | gender | hire_date |
---|---|---|---|---|---|
10008 | 1958-02-19 | Saniya | Kalloufi | M | 1994-09-15 |
好了题目出来了,先建表
然后,插入如下测试代码
INSERT INTO employees VALUES(10001,'1953-09-02','Georgi','Facello','M','1986-06-26'); INSERT INTO employees VALUES(10002,'1964-06-02','Bezalel','Simmel','F','1985-11-21'); INSERT INTO employees VALUES(10003,'1959-12-03','Parto','Bamford','M','1986-08-28'); INSERT INTO employees VALUES(10004,'1954-05-01','Chirstian','Koblick','M','1986-12-01'); INSERT INTO employees VALUES(10005,'1955-01-21','Kyoichi','Maliniak','M','1989-09-12'); INSERT INTO employees VALUES(10006,'1953-04-20','Anneke','Preusig','F','1989-06-02'); INSERT INTO employees VALUES(10007,'1957-05-23','Tzvetan','Zielinski','F','1989-02-10'); INSERT INTO employees VALUES(10008,'1958-02-19','Saniya','Kalloufi','M','1994-09-15'); INSERT INTO employees VALUES(10009,'1952-04-19','Sumant','Peac','F','1985-02-18'); INSERT INTO employees VALUES(10010,'1963-06-01','Duangkaew','Piveteau','F','1989-08-24'); INSERT INTO employees VALUES(10011,'1953-11-07','Mary','Sluis','F','1990-01-22'); ```
然后这道题说的是最晚员工,也就是说hire_date字段的最大值,如何比较max的最大值呢?
我们可以用到max()这个函数,所以我的答案是
select * from employees where hire_date=(select max(hire_date) from employees)`