-- 部門表
create table dept (
id int primary key primary key, -- 部門id
dname varchar(50), -- 部門名稱
loc varchar(50) -- 部門所在地
);
-- 新增4個部門
insert into dept(id,dname,loc) values
(10,'教研部','北京'),
(20,'學工部','上海'),
(30,'銷售部','廣州'),
(40,'財務部','深圳');
-- 職務表，職務名稱，職務描述
create table job (
id int primary key,
jname varchar(20),
description varchar(50)
);
-- 新增4個職務
insert into job (id, jname, description) values
(1, '董事長', '管理整個公司，接單'),
(2, '經理', '管理部門員工'),
(3, '銷售員', '向客人推銷產品'),
(4, '文員', '使用辦公軟體');
-- 員工表
create table emp (
id int primary key, -- 員工id
ename varchar(50), -- 員工姓名
job_id int, -- 職務id
mgr int , -- 上級領導
joindate date, -- 入職日期
salary decimal(7,2), -- 工資
bonus decimal(7,2), -- 獎金
dept_id int, -- 所在部門編號
constraint emp_jobid_ref_job_id_fk foreign key (job_id) references job (id),
constraint emp_deptid_ref_dept_id_fk foreign key (dept_id) references dept (id)
);
-- 新增員工
insert into emp(id,ename,job_id,mgr,joindate,salary,bonus,dept_id) values
(1001,'孫悟空',4,1004,'2000-12-17','8000.00',null,20),
(1002,'盧俊義',3,1006,'2001-02-20','16000.00','3000.00',30),
(1003,'林沖',3,1006,'2001-02-22','12500.00','5000.00',30),
(1004,'唐僧',2,1009,'2001-04-02','29750.00',null,20),
(1005,'李逵',4,1006,'2001-09-28','12500.00','14000.00',30),
(1006,'宋江',2,1009,'2001-05-01','28500.00',null,30),
(1007,'劉備',2,1009,'2001-09-01','24500.00',null,10),
(1008,'豬八戒',4,1004,'2007-04-19','30000.00',null,20),
(1009,'羅貫中',1,null,'2001-11-17','50000.00',null,10),
(1010,'吳用',3,1006,'2001-09-08','15000.00','0.00',30),
(1011,'沙僧',4,1004,'2007-05-23','11000.00',null,20),
(1012,'李逵',4,1006,'2001-12-03','9500.00',null,30),
(1013,'小白龍',4,1004,'2001-12-03','30000.00',null,20),
(1014,'關羽',4,1007,'2002-01-23','13000.00',null,10);
-- 工資等級表
create table salarygrade (
grade int primary key, -- 級別
losalary int, -- 最低工資
hisalary int -- 最高工資
);
-- 新增5個工資等級
insert into salarygrade(grade,losalary,hisalary) values
(1,7000,12000),
(2,12010,14000),
(3,14010,20000),
(4,20010,30000),
(5,30010,99990);
select
emp.`id`,
emp.`ename`,
emp.`salary`,
job.`jname`,
job.`description`
from
emp,
jobwhere emp.`job_id`=job.`id`;
select
emp.`id`,
emp.`ename`,
emp.`salary`,
job.`jname`,
job.`description`,
dept.`dname`,
dept.`loc`
from
emp,
job,
dept
where emp.`job_id`=job.`id` and emp.`dept_id`=dept.`id`;
select
emp.`ename`,
emp.`salary`,
salarygrade.`grade`
from
emp,
salarygrade
where emp.`salary` between salarygrade.`losalary` and salarygrade.`hisalary`;
select
emp.`ename`,
emp.`salary`,
job.`jname`,
job.`description`,
dept.`dname`,
dept.`loc`,
salarygrade.`grade`
from
emp,
job,
dept,
salarygrade
where emp.`job_id`=job.`id` and
emp.`dept_id`=dept.`id` and
emp.`salary` between salarygrade.`losalary` and salarygrade.`hisalary`;
select
dept.`id`,
dept.`dname`,
dept.`loc`,
total
from
dept,
(select
dept_id,
count(id) total
from
empgroup by dept_id) temp
where temp.dept_id=dept.`id`;
select
t1.`ename`,
t1.`mgr`,
t2.`id`,
t2.`ename`
from
emp t1
left join emp t2
on t1.`mgr`=t2.`id`;
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