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SHOW DATABASES;
USE DB1;
SHOW TABLES;
部门表
CREATE TABLE DEPT(
DEPTNO INT PRIMARY KEY,
DNAME VARCHAR(14), -- 部门名称
LOC VARCHAR(13)-- 部门地址
) ;
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
CREATE TABLE EMP(
EMPNO INT PRIMARY KEY, -- 员工编号
ENAME VARCHAR(10), -- 员工姓名
JOB VARCHAR(9), -- 员工工作
MGR INT, -- 员工直属领导编号
HIREDATE DATE, -- 入职时间
SAL DOUBLE, -- 工资
COMM DOUBLE, -- 奖金
DEPTNO INT, -- 所在部门
FOREIGN KEY (DEPTNO) REFERENCES DEPT(DEPTNO)); -- 关联dept表
-- 插入数据
INSERT INTO EMP VALUES(7369,'SMITH','职员',7566,"1980-12-17",800,NULL,20);
INSERT INTO EMP VALUES(7499,'ALLEN','销售员',7698,'1981-02-20',1600,300,30);
INSERT INTO EMP VALUES(7521,'WARD','销售员',7698,'1981-02-22',1250,500,30);
INSERT INTO EMP VALUES(7566,'JONES','经理',7839,'1981-04-02',2975,NULL,20);
INSERT INTO EMP VALUES(7654,'MARTIN','销售员',7698,'1981-09-28',1250,1400,30);
INSERT INTO EMP VALUES(7698,'BLAKE','经理',7839,'1981-05-01',2850,NULL,30);
INSERT INTO EMP VALUES(7782,'CLARK','经理',7839,'1981-06-09',2450,NULL,10);
INSERT INTO EMP VALUES(7788,'SCOTT','职员',7566,'1987-07-03',3000,2000,20);
INSERT INTO EMP VALUES(7839,'KING','董事长',NULL,'1981-11-17',5000,NULL,10);
INSERT INTO EMP VALUES(7844,'TURNERS','销售员',7698,'1981-09-08',1500,50,30);
INSERT INTO EMP VALUES(7876,'ADAMS','职员',7566,'1987-07-13',1100,NULL,20);
INSERT INTO EMP VALUES(7900,'JAMES','职员',7698,'1981-12-03',1250,NULL,30);
INSERT INTO EMP VALUES(7902,'FORD','销售员',7566,'1981-12-03',3000,NULL,20);
INSERT INTO EMP VALUES(7934,'MILLER','职员',7782,'1981-01-23',1300,NULL,10);
工资等级表
CREATE TABLE SALGRADE(
GRADE INT,-- 等级
LOSAL DOUBLE, -- 最低工资
HISAL DOUBLE ); -- 最高工资
INSERT INTO SALGRADE VALUES (1,500,1000);
INSERT INTO SALGRADE VALUES (2,1001,1500);
INSERT INTO SALGRADE VALUES (3,1501,2000);
INSERT INTO SALGRADE VALUES (4,2001,3000);
INSERT INTO SALGRADE VALUES (5,3001,9999);
1、返回部门号及其本部门的最低工资。DEPTNO
SELECT
DEPTNO,
MIN(SAL)
FROM
EMP
GROUP BY
DEPTNO;
2、计算出员工的年薪,并且以年薪排序。
SELECT
*,
SAL*12 A
FROM
EMP
ORDER BY
A ASC;
3、返回员工工作及其从事此工作的最低工资。 JOB SAL(MIN)
SELECT
JOB,
MIN(SAL)
FROM
EMP
GROUP BY
JOB;
4、查找和scott从事相同工作的员工信息
SELECT * FROM
EMP
WHERE
JOB
IN(SELECT
EMP.`JOB`
FROM
EMP
WHERE
EMP.`ENAME`='SCOTT');
5、工资水平多于james的员工信息。
SELECT * FROM
EMP
WHERE
SAL>(SELECT
SAL
FROM
EMP
WHERE
ENAME='JAMES');
6、返回工资大于平均工资的员工信息。
SELECT * FROM
EMP
WHERE
SAL>(
SELECT
SUM(SAL)/
COUNT(JOB)
FROM
EMP);
7、返回销售部(sales)所有员工的姓名。
SELECT
*
FROM
EMP T1,
DEPT T2
WHERE
T1.`DEPTNO`=T2.`DEPTNO`
AND
T2.`DNAME`='SALES';
SELECT deptno FROM dept WHERE dname='sales';
8、返回工资高于30部门所有员工工资水平的员工信息。
SELECT * FROM
EMP
WHERE SAL>(
SELECT
MAX(SAL)
FROM
EMP
WHERE
DEPTNO=30);
EMP.`DEPTNO`=30;
9、返回查找最高工资和最低工资的职员信息
SELECT * FROM
EMP
WHERE
SAL
IN((SELECT MIN(SAL) FROM EMP),(SELECT MAX(SAL) FROM EMP))
AND JOB='职员';
;
10、返回拥有员工的部门名、部门号。
SELECT
DISTINCT
T1.`DNAME`,
T2.`DEPTNO`
FROM
DEPT T1,
EMP T2
WHERE
T2.`DEPTNO`=T1.`DEPTNO`;
11、返回员工的姓名、所在部门名及其工资。emp
SELECT
T1.`ENAME`,
T1.`SAL`,
T2.`DNAME`
FROM
EMP T1,
DEPT T2
WHERE
T2.`DEPTNO`=T1.`DEPTNO`;
12、返回从事职员工作的员工姓名和所在部门名称。
SELECT
T1.`ENAME`,
T2.`DNAME`
FROM
EMP T1,
DEPT T2
WHERE
T2.`DEPTNO`=T1.`DEPTNO`
AND
T1.`JOB`='职员';
13、返回部门号、部门名、部门所在位置及其每个部门的员工总数。
SELECT
T1.`DEPTNO`,
T2.`DNAME`,
T2.`LOC`,
COUNT(*)
FROM
EMP T1,
DEPT T2
WHERE
T2.`DEPTNO`=T1.`DEPTNO`
GROUP BY
T2.`DEPTNO`;
14、返回员工(职员或者销售员)和所属经理的姓名。
SELECT
T1.`ENAME`,
T2.`ENAME`
FROM
EMP T1,
(SELECT
EMP.`ENAME`,
EMP.`EMPNO`
FROM
EMP
WHERE
EMP.`JOB`='经理'
) T2
WHERE
T1.`MGR`=T2.EMPNO;
15、返回员工(职员或者销售员)的入职日期早于其经理入职日期的员工及其经理姓名。
SELECT
T1.`ENAME`,
T2.ENAME
FROM
EMP T1,
(SELECT
EMP.`ENAME`,
EMP.`EMPNO`,
EMP.`HIREDATE`
FROM
EMP
WHERE
EMP.`JOB`='经理') T2
WHERE
T2.`EMPNO`=T1.`MGR`
AND
T2.HIREDATE>T1.`HIREDATE`;
16、返回工资处于第四级别的员工的姓名和工资。
SELECT
T2.`ENAME`,
T2.`SAL`
FROM
EMP T2
WHERE
T2.SAL>(
SELECT
T3.LOSAL
FROM
SALGRADE T3
WHERE
T3.GRADE=4)
AND
T2.SAL<(
SELECT
T3.HISAL
FROM
SALGRADE T3
WHERE
T3.GRADE=4);