部门中薪资超过部门平均薪资的员工姓名及薪资
# 题表
# 建表
create table emp(
id int not null unique auto_increment,
name varchar(20) not null,
sex enum('male','female') not null default 'male', #大部分是男的
age int(3) unsigned not null default 28,
hire_date date not null,
post varchar(50),
post_comment varchar(100),
salary double(15,2),
office int, #一个部门一个屋子
depart_id int
);
#插入记录
#三个部门：教学，销售，运营
insert into emp(name,sex,age,hire_date,post,salary,office,depart_id) values
('jason','male',18,'20170301','张江第一帅形象代言',7300.33,401,1), #以下是教学部
('egon','male',78,'20150302','teacher',1000000.31,401,1),
('kevin','male',81,'20130305','teacher',8300,401,1),
('tank','male',73,'20140701','teacher',3500,401,1),
('owen','male',28,'20121101','teacher',2100,401,1),
('jerry','female',18,'20110211','teacher',9000,401,1),
('nick','male',18,'19000301','teacher',30000,401,1),
('sean','male',48,'20101111','teacher',10000,401,1),
('歪歪','female',48,'20150311','sale',3000.13,402,2),#以下是销售部门
('丫丫','female',38,'20101101','sale',2000.35,402,2),
('丁丁','female',18,'20110312','sale',1000.37,402,2),
('星星','female',18,'20160513','sale',3000.29,402,2),
('格格','female',28,'20170127','sale',4000.33,402,2),
('张野','male',28,'20160311','operation',10000.13,403,3), #以下是运营部门
('程咬金','male',18,'19970312','operation',20000,403,3),
('程咬银','female',18,'20130311','operation',19000,403,3),
('程咬铜','male',18,'20150411','operation',18000,403,3),
('程咬铁','female',18,'20140512','operation',17000,403,3)
;
#ps：如果在windows系统中，插入中文字符，select的结果为空白，可以将所有字符编码统一设置成gbk
select name,salary,post from
(
(select name, salary, post from emp ) as t1
inner join
(select post as post2,avg(salary) as avg from emp group by post) as t2 on t1.post = t2.post2
)
where salary > avg
# 结果：
mysql> select name,salary,post from -> (
-> (select name, salary, post from emp ) as t1
-> inner join
-> (select post as post2,avg(salary) as avg from emp group by post) as t2 on t1.post = t2.post2
-> )
-> where salary > avg;
+-----------+------------+-----------+
| name | salary | post |
+-----------+------------+-----------+
| egon | 1000000.31 | teacher |
| 歪歪 | 3000.13 | sale |
| 星星 | 3000.29 | sale |
| 格格 | 4000.33 | sale |
| 程咬金 | 20000.00 | operation |
| 程咬银 | 19000.00 | operation |
| 程咬铜 | 18000.00 | operation |
| 程咬铁 | 17000.00 | operation |
+-----------+------------+-----------+
8 rows in set (0.00 sec)
