建表
create table employee(
empno int primary key auto_increment ,
ename char(10) ,
job char(6) ,
mgr int ,
hiredate date ,
sal float(10,2),
comm float(10,2),
deptno int );
insert into employee(empno,ename,job,mgr,hiredate,sal,comm,deptno) values
('1001','甘宁','文员','1013','2000-12-17','8000.00',NULL,'20'),
('1002','黛绮丝','销售员','1006','2001-02-20','16000.00','3000.00','30'),
('1003','殷天正','销售员','1006','2001-02-22','12500.00','5000.00','30'),
('1004','刘备','经理','1009','2001-04-02','29750.00',NULL,'20'),
('1005','谢逊','销售员','1006','2001-09-28','12500.00','14000.00','30'),
('1006','关羽','经理','1009','2001-05-01','28500.00',NULL,'30'),
('1007','张飞','经理','1009','2001-09-01','24500.00',NULL,'10'),
('1008','诸葛亮','分析师','1004','2007-04-19','30000.00',NULL,'20'),
('1009','曾阿牛','董事长',NULL,'2001-11-17','50000.00',NULL,'10'),
('1010','韦一笑','销售员','1006','2001-09-08','15000.00','0.00','30'),
('1011','周泰','文员','1008','2007-05-23','11000.00',NULL,'20'),
('1012','程普','文员','1006','2001-12-03','9500.00',NULL,'30'),
('1013','庞统','分析师','1004','2001-12-03','30000.00',NULL,'20'),
('1014','黄盖','文员','1007','2002-01-23','13000.00',NULL,'10');
mysql> create table department(
-> deptno int(5) primary key,
-> dname char(10),
-> loc char(10));
insert into department(deptno,dname,loc) values
('10','教研部','北京'),
('20','学工部','上海'),
('30','销售部','广州'),
('40','财务部','武汉');
mysql> create table salarygrade(
-> grade int(5) primary key auto_increment,
-> losal float(10,2),
-> hisal float(10,2));
Query OK, 0 rows affected, 3 warnings (0.00 sec)
insert into salarygrade(losal,hisal) values
('7000.00','12000.00'),
('12012.00','14000.00'),
('14010.00','20000.00'),
('20010.00','30000.00'),
('30010.00','99990.00');
mysql> create table annualprofit(
-> year year(4) primary key,
-> zz float(10,2));
insert into annualprofit(year,zz) values
('2010','100.00'),
('2011','150.00'),
('2012','250.00'),
('2013','800.00'),
('2014','1000.00');1.查出至少有一个员工的部门。显示部门编号、部门名称、部门位置、部门人数。
select e.deptno,d.dname,d.loc,count(*) as 部门人数 from employee as e,department as d where d.deptno=e.deptno group by e.deptno having count(e.deptno) >=1;
2.列出所有员工的姓名及其直接上级的姓名
SELECT e1.ename AS employee_name, e2.ename AS manager_name FROM employee e1 LEFT JOIN employee e2 ON e1.mgr = e2.empno;
子查询
3.列出受雇日期早于直接上级的所有员工的编号、姓名、部门名称。
SELECT
e1.empno,
e1.ename,
d.dname
FROM
employee e1
JOIN
employee e2 ON e1.mgr = e2.empno
JOIN
department d ON e1.deptno = d.deptno
WHERE
e1.hiredate < e2.hiredate;
4.列出部门名称和这些部门的员工信息，同时列出那些没有员工的部门。
select d.dname,e.* from employee e RIGHT OUTER JOIN department d on d.deptno = e.deptno;
5.列出最低薪金大于15000的各种工作及从事此工作的员工人数。
select job,count(*) as 人数 from employee where sal > 15000 or sal+comm > 15000 group by job;
6.列出在销售部工作的员工的姓名，假定不知道销售部的部门编号。
SELECT
e.ename
FROM
employee e
JOIN
department d ON e.deptno = d.deptno
WHERE
d.dname = '销售部';
7.列出薪金高于公司平均薪金的所有员工信息，所在部门名称，上级领导，工资等级。
SELECT
e.empno,
e.ename,
d.dname,
e.mgr,
e.sal,
sg.grade
FROM
employee e
JOIN
department d ON e.deptno = d.deptno
LEFT JOIN
salarygrade sg ON e.sal BETWEEN sg.losal AND sg.hisal
WHERE
e.sal > (SELECT avg(sal)+sum(comm)/14 FROM employee)
ORDER BY
e.empno;
8.列出与庞统从事相同工作的所有员工及部门名称。
select e.ename,d.dname from employee e inner join department d on e.deptno = d.deptno where e.job = (select job from employee where ename = "庞统" ) ;
9.列出薪金高于在部门30工作的所有员工的薪金，的员工姓名和薪金、部门名称。
select e.ename,e.sal,d.dname from employee e inner join department d
on e.deptno = d.deptno where sal >
(select max(sal+comm) from employee where deptno = 30);
10.查出年份、利润、年度增长比.
SELECT current_year.year, current_year.zz,
CASE WHEN previous_year.zz = 0 THEN NULL
ELSE CONCAT(ROUND(( (current_year.zz - previous_year.zz) / previous_year.zz )*100 ,2 ),'%')
END AS growth_rate
FROM
annualprofit current_year
LEFT JOIN
annualprofit previous_year ON current_year.year = previous_year.year + 1
ORDER BY current_year.year;
