MySQL 部门员工工资表综合练习

前段时间学习了MySQL数据库，今天考了一次数据库的测验，结果没考好，我发现数据库真的是逻辑比代码重要多了！将例题与代码总结于此，以便今后查漏补缺，数据库的知识点实在太密集了，之后再总结到这个MySQL专栏里

员工部门工资表数据库综合练习

数据准备

部门表

-- 创建部门表
DROP TABLE IF EXISTS dept; 
CREATE TABLE dept(
    -- 部门编号
    deptno int PRIMARY KEY, 
    -- 部门名称
    dname VARCHAR(14), 
    -- 部门所在地
    loc VARCHAR(13)
  );
 
-- 向部门表插入数据
INSERT INTO dept VALUES (10,'ACCOUNTING','NEW YORK');
INSERT INTO dept VALUES (20,'RESEARCH','DALLAS');
INSERT INTO dept VALUES (30,'SALES','CHICAGO');
INSERT INTO dept VALUES (40,'OPERATIONS','BOSTON');

员工表

-- 创建员工表
DROP TABLE IF EXISTS emp;
CREATE TABLE emp(
  -- 员工编号
  empno int PRIMARY KEY, 
  -- 员工姓名
  ename VARCHAR(10), 
  -- 工作岗位
  job VARCHAR(9), 
  -- 直属领导
  mgr int, 
  -- 入职时间
  hiredate DATE, 
  -- 工资
  sal double, 
  -- 奖金
  comm double, 
  -- 所属部门
  deptno int
);
 
 
-- 为员工表表添加外键约束
ALTER TABLE emp ADD CONSTRAINT FOREIGN KEY EMP(deptno) REFERENCES dept (deptno);
 
-- 向员工表插入数据
INSERT INTO emp VALUES(7369,'SMITH','CLERK',7902,"1980-12-17",800,NULL,20);
INSERT INTO emp VALUES(7499,'ALLEN','SALESMAN',7698,'1981-02-20',1600,300,30);
INSERT INTO emp VALUES(7521,'WARD','SALESMAN',7698,'1981-02-22',1250,500,30);
INSERT INTO emp VALUES(7566,'JONES','MANAGER',7839,'1981-04-02',2975,NULL,20);
INSERT INTO emp VALUES(7654,'MARTIN','SALESMAN',7698,'1981-09-28',1250,1400,30);
INSERT INTO emp VALUES(7698,'BLAKE','MANAGER',7839,'1981-05-01',2850,NULL,30);
INSERT INTO emp VALUES(7782,'CLARK','MANAGER',7839,'1981-06-09',2450,NULL,10);
INSERT INTO emp VALUES(7788,'SCOTT','ANALYST',7566,'1987-07-03',3000,NULL,20);
INSERT INTO emp VALUES(7839,'KING','PRESIDENT',NULL,'1981-11-17',5000,NULL,10);
INSERT INTO emp VALUES(7844,'TURNER','SALESMAN',7698,'1981-09-08',1500,0,30);
INSERT INTO emp VALUES(7876,'ADAMS','CLERK',7788,'1987-07-13',1100,NULL,20);
INSERT INTO emp VALUES(7900,'JAMES','CLERK',7698,'1981-12-03',950,NULL,30);
INSERT INTO emp VALUES(7902,'FORD','ANALYST',7566,'1981-12-03',3000,NULL,20);
INSERT INTO emp VALUES(7934,'MILLER','CLERK',7782,'1981-01-23',1300,NULL,10);

工资等级表

-- 创建工资等级表
DROP TABLE IF EXISTS salgrade;
CREATE TABLE salgrade(
  -- 等级
  grade int, 
  -- 最低工资
  losal double, 
  -- 最高工资
  hisal double
);
 
-- 向工资等级表插入数据
INSERT INTO salgrade VALUES (1,700,1200);
INSERT INTO salgrade VALUES (2,1201,1400);
INSERT INTO salgrade VALUES (3,1401,2000);
INSERT INTO salgrade VALUES (4,2001,3000);
INSERT INTO salgrade VALUES (5,3001,9999);