多表练习:
create database ali;
use ali;
#部门表
CREATE TABLE dept (
id INT PRIMARY KEY,
#部门id
dname VARCHAR (50),
#部门名称
loc VARCHAR (50) #部门所在地
);
#添加4个部门
INSERT INTO dept(id,dname,loc) VALUES
(10,'教研','北京'),
(20,'学工','上海'),
(30,'销售','广州'),
(40,'财务','深圳');
#职务表,职务名称,职务描述
CREATE TABLE job (
id INT PRIMARY KEY,
jname VARCHAR(20),
description VARCHAR(50)
);
#添加4个职务
INSERT INTO job (id, jname, description) VALUES
(1, '董事长', '管理整个公司,接单'),
(2, '经理', '管理部门员工'),
(3, '销售员', '向客人推销产品'),
(4, '文员', '使用办公软件');
#员工表
CREATE TABLE emp (
id INT PRIMARY KEY, #员工id
ename VARCHAR(20), #员工姓名
job_id INT, #职务id
mgr INT , #上级领导
joindate DATE, #入职日期
salary DECIMAL(7,2), #工资
bonus DECIMAL(7,2), #奖金
dept_id INT #所在部门编号
);
#添加员工
INSERT INTO emp(id,ename,job_id,mgr,joindate,salary,bonus,dept_id) VALUES
(1001,'孙悟空',4,1004,'2000-12-17','8000.00',NULL,20),
(1002,'卢俊义',3,1006,'2001-02-20','16000.00','3000.00',30),
(1003,'林冲',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,'刘备',2,1009,'2001-09-01','24500.00',NULL,10),
(1008,'猪八戒',4,1004,'2007-04-19','30000.00',NULL,20),
(1009,'罗贯中',1,NULL,'2001-11-17','50000.00',NULL,10),
(1010,'吴用',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,'小白龙',4,1004,'2001-12-03','30000.00',NULL,20),
(1014,'关羽',4,1007,'2002-01-23','13000.00',NULL,10);
#工资等级表
CREATE TABLE salarygrade (
grade INT PRIMARY KEY,
#级别
losalary INT,
#最低工资
hisalary INT#最高工资
) ;
#添加5个工资等级
INSERT INTO salarygrade(grade,losalary,hisalary) VALUES
(1,7000,12000),
(2,12010,14000),
(3,14010,20000),
(4,20010,30000),
(5,30010,99990);
#查询所有员工信息。查询员工编号,员工姓名,工资,职务名称,职务描述
select e.id,ename,jname ,description from emp e,job j where e.job_id=j.id ;
#查询员工编号,员工姓名,工资,职务名称,职务描述,部门名称,部门位置(三表可选座)
select e.id,ename,jname,description ,dname,loc from emp e,job j,dept d where e.job_id=j.id and e.dept_id=d.id;
#查询员工姓名,工资,工资等级
select e.ename,e.salary,s.grade from emp e,salarygrade s where e.salary between s.losalary and s.hisalary;
#查询员工姓名,工资,职务名称,职务描述,部门名称,部门位置,工资等级(四表联查选做)
select e.id,ename,jname,description ,dname,loc,s.grade from emp e,job j,dept d, salarygrade s where e.job_id=j.id and e.dept_id=d.id and e.salary and e.salary between s.losalary and s.hisalary;
#查询所有员工的姓名及其直接上级的姓名,没有领导的员工也需要查询(这题讲过哦!!)
select a.ename,(select ename from emp b where b.id=a.mgr) as boss_name from emp a;
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