经典查询练手第四篇

HR@PROD2> desc EMPLOYEES
Name						       Null?	Type
----------------------------------------------------- -------- ------------------------------------
EMPLOYEE_ID					       NOT NULL NUMBER(6)
FIRST_NAME							VARCHAR2(20)
LAST_NAME					       NOT NULL VARCHAR2(25)
EMAIL						       NOT NULL VARCHAR2(25)
PHONE_NUMBER							VARCHAR2(20)
HIRE_DATE					       NOT NULL DATE
JOB_ID 					       NOT NULL VARCHAR2(10)
SALARY 							NUMBER(8,2)
COMMISSION_PCT 						NUMBER(2,2)
MANAGER_ID							NUMBER(6)
DEPARTMENT_ID							NUMBER(4)

HR@PROD2> desc DEPARTMENTS
Name						       Null?	Type
----------------------------------------------------- -------- ------------------------------------
DEPARTMENT_ID					       NOT NULL NUMBER(4)
DEPARTMENT_NAME				       NOT NULL VARCHAR2(30)
MANAGER_ID							NUMBER(6)
LOCATION_ID							NUMBER(4)

HR@PROD2> DESC REGIONS
Name						       Null?	Type
----------------------------------------------------- -------- ------------------------------------
REGION_ID					       NOT NULL NUMBER
REGION_NAME							VARCHAR2(25)

HR@PROD2> desc locations
Name						       Null?	Type
----------------------------------------------------- -------- ------------------------------------
LOCATION_ID					       NOT NULL NUMBER(4)
STREET_ADDRESS 						VARCHAR2(40)
POSTAL_CODE							VARCHAR2(12)
CITY						       NOT NULL VARCHAR2(30)
STATE_PROVINCE 						VARCHAR2(25)
COUNTRY_ID							CHAR(2)

HR@PROD2> desc jobs
Name						       Null?	Type
----------------------------------------------------- -------- ------------------------------------
JOB_ID 					       NOT NULL VARCHAR2(10)
JOB_TITLE					       NOT NULL VARCHAR2(35)
MIN_SALARY							NUMBER(6)
MAX_SALARY							NUMBER(6)

1. 各个部门平均、最大、最小工资、人数，按照部门号升序排列。

2. 各个部门中工资大于5000的员工人数。

3. 各个部门平均工资和人数，按照部门名字升序排列。

4. 列出每个部门中有同样工资的员工的统计信息，列出他们的部门号，工资，人数。

5. 列出同部门中工资高于1000 的员工数量超过2 人的部门，显示部门名字、地区名称。

6. 哪些员工的工资，高于整个公司的平均工资，列出员工的名字和工资（降序）。

7. 哪些员工的工资，介于50号 和80号部门平均工资之间。

8. 所在部门平均工资高于5000 的员工名字。

9. 列出各个部门中工资最高的员工的信息：名字、部门号、工资。

10. 最高的部门平均工资是多少。

1. 各个部门平均、最大、最小工资、人数，按照部门号升序排列。
HR@PROD2> select max(salary) msal,min(salary) isal,avg(salary) asal,count(*)
from employees
group by department_id
order by department_id asc;

MSAL ISAL ASAL COUNT(*)
---------- ---------- ---------- ----------
4400 4400 4400 1
13000 6000 9500 2
11000 2500 4150 6
6500 6500 6500 1
8200 2100 3475.55556 45
9000 4200 5760 5
10000 10000 10000 1
14000 6100 8955.88235 34
24000 17000 19333.3333 3
12008 6900 8601.33333 6
12008 8300 10154 2
7000 7000 7000 1

2. 各个部门中工资大于5000的员工人数。
HR@PROD2> select department_id,count(*)
from employees
where salary>5000
group by department_id
order by department_id;

DEPARTMENT_ID COUNT(*)
------------- ----------
20 2
30 1
40 1
50 5
60 2
70 1
80 34
90 3
100 6
110 2
1

11 rows selected.

3. 各个部门平均工资和人数，按照部门名字升序排列。
HR@PROD2> select e.department_id,d.department_name,avg(e.salary) asal,count(*)
from employees e,departments d
where e.department_id=d.department_id
group by e.department_id,d.department_name
order by d.department_name;

DEPARTMENT_ID DEPARTMENT_NAME ASAL COUNT(*)
------------- ------------------------------ ---------- ----------
110 Accounting 10154 2
10 Administration 4400 1
90 Executive 19333.3333 3
100 Finance 8601.33333 6
40 Human Resources 6500 1
60 IT 5760 5
20 Marketing 9500 2
70 Public Relations 10000 1
30 Purchasing 4150 6
80 Sales 8955.88235 34
50 Shipping 3475.55556 45

11 rows selected.

4. 列出每个部门中有同样工资的员工的统计信息，列出他们的部门号，工资，人数。
HR@PROD2> select a.department_id,a.salary,count(*)
from employees a,employees b
where a.department_id=b.department_id and a.employee_id <> b.employee_id and a.salary=b.salary
group by a.department_id,a.salary
order by a.department_id; 2 3 4 5

DEPARTMENT_ID SALARY COUNT(*)
------------- ---------- ----------
50 2200 2
50 2400 2
50 2500 20
50 2600 6
50 2700 2
50 2800 6
50 2900 2
50 3000 2
50 3100 6
50 3200 12
50 3300 2
50 3600 2
60 4800 2
80 6200 2
80 7000 2
80 7500 2
80 8000 2
80 9000 2
80 9500 6
80 10000 6
80 10500 2
80 11000 2
90 17000 2

23 rows selected.

5. 列出同部门中工资高于1000 的员工数量超过2 人的部门，显示部门名字、地区名称。
HR@PROD2> select d.department_name,l.city,count(*)
from departments d,locations l,employees e
where d.location_id=l.location_id and e.department_id=d.department_id and salary>1000
group by d.department_name,l.city
having count(*)>2; 2 3 4 5

DEPARTMENT_NAME CITY COUNT(*)
------------------------------ ------------------------------ ----------
IT Southlake 5
Sales Oxford 34
Shipping South San Francisco 45
Purchasing Seattle 6
Executive Seattle 3
Finance Seattle 6

6 rows selected.

6. 哪些员工的工资，高于整个公司的平均工资，列出员工的名字和工资（降序）。
HR@PROD2> select first_name||' '||last_name name, salary
from employees e,(select avg(salary) asal from employees ) a
where e.salary>a.asal;

NAME SALARY
---------------------------------------------- ----------
Michael Hartstein 13000
Susan Mavris 6500
Hermann Baer 10000
Shelley Higgins 12008
William Gietz 8300
Steven King 24000
Neena Kochhar 17000
Lex De Haan 17000
Alexander Hunold 9000
Nancy Greenberg 12008
Daniel Faviet 9000
John Chen 8200
Ismael Sciarra 7700
Jose Manuel Urman 7800
Luis Popp 6900
Den Raphaely 11000
Matthew Weiss 8000
Adam Fripp 8200
Payam Kaufling 7900
Shanta Vollman 6500
John Russell 14000
Karen Partners 13500
Alberto Errazuriz 12000
Gerald Cambrault 11000
Eleni Zlotkey 10500
Peter Tucker 10000
David Bernstein 9500
Peter Hall 9000
Christopher Olsen 8000
Nanette Cambrault 7500
Oliver Tuvault 7000
Janette King 10000
Patrick Sully 9500
Allan McEwen 9000
Lindsey Smith 8000
Louise Doran 7500
Sarath Sewall 7000
Clara Vishney 10500
Danielle Greene 9500
Mattea Marvins 7200
David Lee 6800
Lisa Ozer 11500
Harrison Bloom 10000
Tayler Fox 9600
William Smith 7400
Elizabeth Bates 7300
Ellen Abel 11000
Alyssa Hutton 8800
Jonathon Taylor 8600
Jack Livingston 8400
Kimberely Grant 7000

51 rows selected.

--或者如下方法
select first_name||' '||last_name name,salary
from employees
where salary > (select avg(salary) from employees);

7. 哪些员工的工资，介于50号 和80号部门平均工资之间。
HR@PROD2> select first_name||' '||last_name name
from employees
where salary between (select avg(salary) from employees where department_id='50') and (select avg(salary) from employees where department_id='80');

NAME
----------------------------------------------
Jennifer Whalen
Pat Fay
Susan Mavris
William Gietz
Bruce Ernst
David Austin
Valli Pataballa
Diana Lorentz
John Chen
Ismael Sciarra
Jose Manuel Urman
Luis Popp
Matthew Weiss
Adam Fripp
Payam Kaufling
Shanta Vollman
Kevin Mourgos
Renske Ladwig
Trenna Rajs
Christopher Olsen
Nanette Cambrault
Oliver Tuvault
Lindsey Smith
Louise Doran
Sarath Sewall
Mattea Marvins
David Lee
Sundar Ande
Amit Banda
William Smith
Elizabeth Bates
Sundita Kumar
Alyssa Hutton
Jonathon Taylor
Jack Livingston
Kimberely Grant
Charles Johnson
Nandita Sarchand
Alexis Bull
Kelly Chung
Jennifer Dilly
Sarah Bell
Britney Everett

43 rows selected.

8. 所在部门平均工资高于5000 的员工名字。
HR@PROD2> select first_name||' '||last_name name,salary
from employees
where department_id in (select department_id from employees group by department_id having avg(salary)>5000);

NAME SALARY
---------------------------------------------- ----------
Nancy Greenberg 12008
Daniel Faviet 9000
John Chen 8200
Ismael Sciarra 7700
Jose Manuel Urman 7800
Luis Popp 6900
Michael Hartstein 13000
Pat Fay 6000
Hermann Baer 10000
Steven King 24000
Neena Kochhar 17000
Lex De Haan 17000
Shelley Higgins 12008
William Gietz 8300
Susan Mavris 6500
John Russell 14000
Karen Partners 13500
Alberto Errazuriz 12000
Gerald Cambrault 11000
Eleni Zlotkey 10500
Peter Tucker 10000
David Bernstein 9500
Peter Hall 9000
Christopher Olsen 8000
Nanette Cambrault 7500
Oliver Tuvault 7000
Janette King 10000
Patrick Sully 9500
Allan McEwen 9000
Lindsey Smith 8000
Louise Doran 7500
Sarath Sewall 7000
Clara Vishney 10500
Danielle Greene 9500
Mattea Marvins 7200
David Lee 6800
Sundar Ande 6400
Amit Banda 6200
Lisa Ozer 11500
Harrison Bloom 10000
Tayler Fox 9600
William Smith 7400
Elizab
b879
eth Bates 7300
Sundita Kumar 6100
Ellen Abel 11000
Alyssa Hutton 8800
Jonathon Taylor 8600
Jack Livingston 8400
Charles Johnson 6200
Alexander Hunold 9000
Bruce Ernst 6000
David Austin 4800
Valli Pataballa 4800
Diana Lorentz 4200

54 rows selected.

9. 列出各个部门中工资最高的员工的信息：名字、部门号、工资。
HR@PROD2> select e.first_name||' '||e.last_name name,e.department_id,e.salary
from employees e,(select department_id,max(salary) msal from employees group by department_id) s
where e.department_id=s.department_id and e.salary=s.msal;

NAME DEPARTMENT_ID SALARY
---------------------------------------------- ------------- ----------
Nancy Greenberg 100 12008
Den Raphaely 30 11000
Michael Hartstein 20 13000
Hermann Baer 70 10000
Steven King 90 24000
Shelley Higgins 110 12008
Adam Fripp 50 8200
Susan Mavris 40 6500
John Russell 80 14000
Jennifer Whalen 10 4400
Alexander Hunold 60 9000

11 rows selected.

--另一种简单的方法
SELECT FIRST_NAME || ' ' || LAST_NAME AS NAME,SALARY,DEPARTMENT_ID
FROM EMPLOYEES
WHERE (DEPARTMENT_ID,SALARY) IN (SELECT DEPARTMENT_ID,MAX(SALARY) FROM EMPLOYEES GROUP BY DEPARTMENT_ID);

10. 最高的部门平均工资是多少。
HR@PROD2> select max(avg(salary)) from employees group by department_id;

MAX(AVG(SALARY))
----------------
19333.3333