Oracle+SQL:经典查询练手四篇

WANGJING

17 rows selected

--------4．列出受雇日期早于其直接上级的所有员工。----------

SQL> select a.ename from emp a where a.hiredate<(select hiredate from emp b where b.empno=a.mgr); ENAME

---------- SMITH ALLEN WARD JONES BLAKE CLARK

6 rows selected

--------5．列出部门名称和这些部门的员工信息，同时列出那些没有员工的部门----------

SQL> select a.dname,b.empno,b.ename,b.job,b.mgr,b.hiredate,b.sal,b.deptno

2 from dept a left join emp b on a.deptno=b.deptno;

DNAME EMPNO ENAME JOB MGR HIREDATE SAL DEPTNO

-------------- ----- ---------- --------- ----- ----------- --------- ------

RESEARCH 7369 SMITH CLERK 7902 1980-12-17 800.00 20 SALES 7499 ALLEN SALESMAN 7698 1981-2-20 1600.00 30 SALES 7521 WARD SALESMAN 7698 1981-2-22 1250.00 30 RESEARCH 7566 JONES MANAGER 7839 1981-4-2 2975.00 20 SALES 7654 MARTIN SALESMAN 7698 1981-9-28 1250.00 30 SALES 7698 BLAKE MANAGER 7839 1981-5-1 2850.00 30

ACCOUNTING 7782 CLARK MANAGER 7839 1981-6-9 2450.00 10 RESEARCH 7788 SCOTT ANALYST 7566 1987-4-19 4000.00 20 ACCOUNTING 7839 KING PRESIDENT 1981-11-17 5000.00 10 SALES 7844 TURNER SALESMAN 7698 1981-9-8 1500.00 30 RESEARCH 7876 ADAMS CLERK 7788 1987-5-23 1100.00 20 SALES 7900 JAMES CLERK 7698 1981-12-3 950.00 30

RESEARCH 7902 FORD ANALYST 7566 1981-12-3 3000.00 20 ACCOUNTING 7934 MILLER CLERK 7782 1982-1-23 1300.00 10

ACCOUNTING 102 EricHu Developer 1455 2011-5-26 1 5500.00 10 ACCOUNTING 104 huyong PM 1455 2011-5-26 1 5500.00 10

ACCOUNTING 105 WANGJING Developer 1455 2011-5-26 1 5500.00 10 50abc

OPERATIONS

Developer

20 rows selected

--------6．列出所有“CLERK”（办事员）的姓名及其部门名称。---------- SQL> select a.ename,b.dname from emp a join dept b on a.deptno=b.deptno and a.job='CLERK'; ENAME DNAME

---------- -------------- SMITH RESEARCH ADAMS RESEARCH JAMES SALES

MILLER ACCOUNTING

--------7．列出最低薪金大于1500的各种工作。----------

SQL> select distinct job as HighSalJob from emp group by job having min(sal)>1500; HIGHSALJOB ---------- ANALYST Developer MANAGER PM

PRESIDENT

--------8．列出在部门“SALES”（销售部）工作的员工的姓名，假定不知道销售部的部门编号。----------

SQL> select ename from emp where deptno=(select deptno from dept where dname='SALES'); ENAME

---------- ALLEN WARD MARTIN BLAKE TURNER JAMES

6 rows selected

--------9．列出薪金高于公司平均薪金的所有员工。----------

SQL> select ename from emp where sal>(select avg(sal) from emp); ENAME

---------- JONES BLAKE SCOTT KING FORD EricHu huyong WANGJING

8 rows selected

--------10．列出与“SCOTT”从事相同工作的所有员工。--------

SQL> select ename from emp where job=(select job from emp where ename='SCOTT'); ENAME

---------- SCOTT FORD

--------11．列出薪金等于部门30中员工的薪金的所有员工的姓名和薪金。---------

SQL> select a.ename,a.sal from emp a where a.sal in (select b.sal 2 from emp b where b.deptno=30) and a.deptno<>30; ENAME SAL

---------- ---------

--------12．列出薪金高于在部门30工作的所有员工的薪金的员工姓名和薪金。---------

SQL> select ename,sal from emp where sal>(select max(sal) from emp where deptno=30); ENAME SAL

---------- --------- JONES 2975.00 SCOTT 4000.00 KING 5000.00 FORD 3000.00 EricHu 5500.00 huyong 5500.00 WANGJING 5500.00 7 rows selected

--------13．列出在每个部门工作的员工数量、平均工资和平均服务期限。---------

SQL> select (select b.dname from dept b where a.deptno=b.deptno) as d

eptname ,count(deptno) as deptcount,avg(sal) as deptavgsal 2 from emp a group by deptno; DEPTNAME DEPTCOUNT DEPTAVGSAL

-------------- ---------- ---------- ACCOUNTING 6 4208.33333 RESEARCH 5 2375 SALES 6 1566.66666

--------14．列出所有员工的姓名、部门名称和工资。---------

SQL> select a.ename,(select b.dname from dept b where b.deptno=a.deptno) as deptname,sal from emp a;

ENAME DEPTNAME SAL

---------- -------------- --------- SMITH RESEARCH 800.00 ALLEN SALES 1600.00 WARD SALES 1250.00

JONES RESEARCH 2975.00 MARTIN SALES 1250.00 BLAKE SALES 2850.00

CLARK ACCOUNTING 2450.00 SCOTT RESEARCH 4000.00 KING ACCOUNTING 5000.00 TURNER SALES 1500.00 ADAMS RESEARCH 1100.00 JAMES SALES 950.00 FORD RESEARCH 3000.00

MILLER ACCOUNTING 1300.00 EricHu ACCOUNTING 5500.00 huyong ACCOUNTING 5500.00 WANGJING ACCOUNTING 5500.00

17 rows selected

--------15．列出所有部门的详细信息和部门人数。---------

SQL> select a.deptno,a.dname,a.loc,(select count(deptno) from emp b where b.deptno=a.deptno group by b.deptno) as deptcount from dept a; DEPTNO DNAME LOC DEPTCOUNT

------ -------------- ------------- ---------- 10 ACCOUNTING NEW YORK 6 20 RESEARCH DALLAS 5 30 SALES CHICAGO 6 40 OPERATIONS BOSTON 50 50abc 50def