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MySQL数据库实操教程(34)——SQL语句综合练习

2019-08-18 12:55 1346 查看
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在本节教程中,我们练习常用SQL语句。

数据准备

-- 原创作者:谷哥的小弟
-- 博客地址:http://blog.csdn.net/lfdfhl

-- 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');

-- 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);

-- 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);

图示如下:

练习题目

-- 原创作者:谷哥的小弟
-- 博客地址:http://blog.csdn.net/lfdfhl

-- 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');

-- 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);

-- 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);
-- 01、查询部门编号为30的部门的员工详细信息
SELECT * FROM emp WHERE deptno = 30;

-- 02、查询从事clerk工作的员工的编号、姓名以及其部门号
SELECT empno,ename,deptno FROM emp WHERE job = 'clerk';

-- 03、查询奖金多于基本工资的员工的信息
SELECT * FROM emp WHERE comm > sal;

-- 04、查询奖金多于基本工资60%的员工的信息
SELECT * FROM emp WHERE comm > sal * 0.6;

-- 05、查询部门编号为10的部门经理和部门编号为20的部门中工作为CLERK的职员信息
SELECT * FROM emp WHERE deptno = 10 AND job='MANAGER' OR deptno = 20 AND job = 'CLERK';

-- 06、查询部门编号为10的部门经理或部门编号为20的部门工作为CLERK的职员信息或者既不是经理也不是CLERK但是工资高于2000的员工信息
SELECT * FROM emp WHERE deptno = 10 AND job='MANAGER'
OR deptno = 20 AND job = 'CLERK'
OR job NOT IN ('MANAGER','CLERK') AND sal > 2000 ;

-- 07、查询获得奖金的员工的信息
SELECT * FROM emp WHERE comm > 0;

-- 08、查询奖金少于100或者没有获得奖金的员工的信息
SELECT * FROM emp WHERE comm < 100 OR comm IS NULL;

-- 09、查询姓名以A、B、S开头的员工的信息
SELECT * FROM emp WHERE ename LIKE 'A%' OR ename LIKE 'B%' OR ename LIKE 'S%';

-- 10、查询找到姓名长度为6个字符的员工的信息
SELECT * FROM emp WHERE LENGTH(ename) = 6;
SELECT * FROM emp WHERE ename LIKE '______';

-- 11、查询姓名中不包含R字符的员工信息。
SELECT * FROM emp WHERE ename NOT LIKE '%R%';

-- 12、查询员工的详细信息并按姓名排序
SELECT * FROM emp ORDER BY ename ASC;

-- 13、查询员工的信息并按工作降序工资升序排列
SELECT * FROM emp ORDER BY job DESC , sal ASC;

-- 14、计算员工的日薪(按30天计)
SELECT ename,sal/30 AS '日薪' FROM emp;
select ename,TRUNCATE(sal/30,2) '日薪' FROM emp;

-- 15、查询姓名中包含字符A的员工的信息
SELECT * FROM  emp WHERE  ename LIKE '%A%';

-- 16、查询拥有员工的部门的部门名和部门号
SELECT DISTINCT d.dname, d.deptno FROM dept d,emp e WHERE d.deptno = e.deptno;

-- 17、查询工资多于smith的员工信息。
SELECT *FROM emp WHERE sal > (SELECT sal FROM emp WHERE ename = 'smith');

-- 18、查询员工和及其所属经理的姓名
SELECT e.ename , m.ename AS mgrname FROM emp e LEFT OUTER JOIN emp m ON e.mgr = m.empno;
SELECT e.ename , m.ename AS mgrname FROM emp e , emp m WHERE e.mgr = m.empno;

-- 19、查询雇佣日期早于其经理雇佣日期的员工及其经理姓名
SELECT e.ename,m.ename AS mgrname FROM emp e,emp m WHERE e.mgr=m.empno AND e.hiredate < m.hiredate;
SELECT e.ename,m.ename AS mgrname FROM emp e INNER JOIN emp m ON e.mgr = m.empno WHERE e.hiredate < m.hiredate;

-- 20、查询员工姓名及其所在的部门名称
SELECT e.ename,d.dname FROM emp e , dept d WHERE e.deptno = d.deptno;

-- 21、查询工作为clerk的员工姓名及其所在部门名称
SELECT e.ename,d.dname FROM emp e , dept d WHERE e.deptno = d.deptno AND e.job = 'CLERK';

-- 22、查询各部门号及其部门中的最低工资
SELECT deptno ,MIN(sal) AS minsal FROM emp GROUP BY deptno;

-- 23、查询销售部sales的所有员工的姓名
SELECT ename FROM emp WHERE deptno=(SELECT deptno FROM dept WHERE dname='sales');
SELECT e.ename FROM emp e,dept d WHERE e.deptno = d.deptno AND d.dname = 'sales';

-- 24、查询工资水平大于平均工资的员工
SELECT * FROM emp e WHERE e.sal > (SELECT AVG(sal) FROM emp);

-- 25、查询与SCOTT从事相同工作的员工。
SELECT * FROM emp WHERE job = (SELECT job FROM emp WHERE ename = 'scott');

-- 26、查询与部门编号为30的员工工资水平相同的员工信息
SELECT * FROM emp WHERE sal IN (SELECT sal FROM emp WHERE deptno = 30);

-- 27、查询工资高于部门编号为30的部门所有员工工资水平的员工信息
SELECT * FROM emp WHERE sal > ALL(SELECT sal FROM emp WHERE deptno = 30);
SELECT * FROM emp WHERE sal > (SELECT MAX(sal) FROM emp WHERE deptno = 30);

-- 28、查询部门号、部门名、部门所在位置及其每个部门的员工总数
SELECT d.deptno,d.dname,d.loc,COUNT(e.deptno) AS number FROM dept d,emp e
WHERE d.deptno = e.deptno GROUP BY e.deptno;

-- 29、查询员工的姓名、工资及其所属部门
SELECT ename,dname,sal FROM emp ,dept WHERE emp.deptno = dept.deptno;

-- 30、查询员工的详细信息(含部门名)
SELECT e.* , d.dname FROM emp e, dept d WHERE e.deptno = d.deptno;

-- 31、查询各工作名称以及从事此工作的最低工资
SELECT job , MIN(sal) AS minsal FROM emp GROUP BY job;

-- 32、计算员工的年薪并且以年薪排序
SELECT ename, sal * 12 AS yearSalary FROM emp ORDER BY yearSalary;

-- 33、查询工资为第4级别的员工的姓名及其工资
SELECT ename,sal FROM emp e ,salgrade s WHERE e.sal >= s.losal AND e.sal <= s.hisal AND s.grade = 4;
SELECT emp.ename,emp.sal FROM emp ,(SELECT losal,hisal FROM salgrade WHERE grade=4) g WHERE emp.sal BETWEEN g.losal AND g.hisal;

-- 34、查询工资为第3等级的职员名字、工资、所属部门以及部门所在地
SELECT ename ,sal ,dname ,loc FROM emp,dept,salgrade
WHERE emp.deptno = dept.deptno AND grade = 3
AND sal >= losal AND sal < hisal;

-- 35、查询工资等级大于smith的员工的信息
SELECT e.* FROM emp e, salgrade s
WHERE s.hisal < e.sal AND s.grade = (SELECT grade FROM salgrade s ,emp e
WHERE s.losal < e.sal AND s.hisal > e.sal AND e.ename = 'smith');

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