注：此文章来自“博客园”博主，在此借鉴
1、问题背景
本文中的SQL语句都是基于下面几张表的，这也是比较经典的用于数据库教学的数据库例子。
（1）/*员工人事表employee */
|
emp_no
|
char(5)
|
Not null
|
primary key
|
员工编号
|
|
emp_name
|
char(10)
|
Not null
|
|
员工姓名
|
|
sex
|
char(1)
|
Not null
|
|
性别
|
|
dept
|
char(4)
|
Not null
|
|
所属部门
|
|
title
|
char(6)
|
Not null
|
|
职称
|
|
date_hired
|
datetime
|
Not null
|
|
到职日
|
|
birthday
|
datetime
|
Null
|
|
生日
|
|
salary
|
int
|
Not null
|
|
薪水
|
|
addr
|
char(50)
|
null
|
|
住址
|
|
Mod_date
|
datetime
|
Default(getdate())
|
操作者
|
（2）/*客户表customer */
|
cust_id
|
char(5)
|
Not null
|
primary key
|
客户号
|
|
cust_name
|
char(20)
|
Not null,
|
|
客户名称
|
|
addr
|
char(40)
|
Not null,
|
|
客户住址
|
|
tel_no
|
char(10)
|
Not null,
|
|
客户电话
|
|
zip
|
char(6)
|
null
|
|
邮政编码
|
（3）/*销售主表sales */
|
order_no
|
int
|
Not null
|
primary key
|
订单编号
|
|
cust_id
|
char(5)
|
Not null,
|
|
客户号
|
|
sale_id
|
char(5)
|
Not null,
|
|
业务员编号
|
|
tot_amt
|
numeric(9,2)
|
Not null,
|
|
订单金额
|
|
order_date
|
datetime
|
Not null,
|
|
订货日期
|
|
ship_date
|
datetime
|
Not null,
|
|
出货日期
|
|
invoice_no
|
char(10)
|
Not null
|
|
发票号码
|
（4）/*销货明细表sale_item */
|
order_no
|
int
|
Not null,
|
primary key
|
订单编号
|
|
prod_id
|
char(5)
|
Not null,
|
产品编号
|
|
qty
|
int
|
Not null
|
|
销售数量
|
|
unit_price
|
numeric(7,2)
|
Not null
|
|
单价
|
|
order_date
|
datetime
|
null
|
|
订单日期
|
（5）/*产品名称表product */
|
prod_id
|
char(5)
|
Not null
|
primary key
|
产品编号
|
|
prod_name
|
char(20)
|
Not null
|
|
产品名称
|
2、各种查询的SQL语句
问题1、查找员工的编号、姓名、部门和出生日期，如果出生日期为空值，显示日期不详,并按部门排序输出,日期格式为yyyy-mm-dd。
问题2、查找与喻自强在同一个单位的员工姓名、性别、部门和职称
select emp_no ,emp_name ,dept ,
isnull(convert(char(10),birthday,120),'日期不详') birthday
from employee
order by dept
问题3、按部门进行汇总，统计每个部门的总工资
select dept,sum(salary)
from employee
group by dept
问题4、查找商品名称为14寸显示器商品的销售情况，显示该商品的编号、销售数量、单价和金额
select a.prod_id,qty,unit_price,unit_price*qty totprice
from sale_item a,product b
where a.prod_id=b.prod_id and prod_name='14寸显示器'
问题5、在销售明细表中按产品编号进行汇总，统计每种产品的销售数量和金额
select prod_id,sum(qty) totqty,sum(qty*unit_price) totprice
from sale_item
group by prod_id
问题6、使用convert函数按客户编号统计每个客户1996年的订单总金额
select cust_id,sum(tot_amt) totprice
from sales
where convert(char(4),order_date,120)='1996'
group by cust_id
问题7、查找有销售记录的客户编号、名称和订单总额
select a.cust_id,cust_name,sum(tot_amt) totprice
from customer a,sales b
where a.cust_id=b.cust_id
group by a.cust_id,cust_name
问题8、查找在1997年中有销售记录的客户编号、名称和订单总额
select a.cust_id,cust_name,sum(tot_amt) totprice
from customer a,sales b
where a.cust_id=b.cust_id and convert(char(4),order_date,120)='1997'
group by a.cust_id,cust_name
问题9、查找一次销售最大的销售记录
select order_no,cust_id,sale_id,tot_amt
from sales
where tot_amt=
(select max(tot_amt)
from sales)
问题10、查找至少有3次销售的业务员名单和销售日期
select emp_name,order_date
from employee a,sales b
where emp_no=sale_id and a.emp_no in
(select sale_id
from sales
group by sale_id
having count(*)>=3)
order by emp_name
问题11、用存在量词查找没有订货记录的客户名称
select cust_name
from customer a
where not exists
(select *
from sales b
where a.cust_id=b.cust_id)
问题12、使用左外连接查找每个客户的客户编号、名称、订货日期、订单金额；订货日期不要显示时间，日期格式为yyyy-mm-dd；按客户编号排序，同一客户再按订单降序排序输出
select a.cust_id,cust_name,convert(char(10),order_date,120),tot_amt
from customer a left outer join sales b on a.cust_id=b.cust_id
order by a.cust_id,tot_amt desc
问题13、查找16M DRAM的销售情况，要求显示相应的销售员的姓名、性别，销售日期、销售数量和金额，其中性别用男、女表示
select emp_name 姓名, 性别= case a.sex when 'm' then '男'
when 'f' then '女'
else '未'
end,
销售日期= isnull(convert(char(10),c.order_date,120),'日期不详'),
qty 数量, qty*unit_price as 金额
from employee a, sales b, sale_item c,product d
where d.prod_name='16M DRAM' and d.pro_id=c.prod_id and
a.emp_no=b.sale_id and b.order_no=c.order_no
问题14、查找每个人的销售记录，要求显示销售员的编号、姓名、性别、产品名称、数量、单价、金额和销售日期
select emp_no 编号,emp_name 姓名, 性别= case a.sex when 'm' then '男'
when 'f' then '女'
else '未'
end,
prod_name 产品名称,销售日期= isnull(convert(char(10),c.order_date,120),'日期不详'),
qty 数量, qty*unit_price as 金额
from employee a left outer join sales b on a.emp_no=b.sale_id , sale_item c,product d
where d.pro_id=c.prod_id and b.order_no=c.order_no
问题15、查找销售金额最大的客户名称和总货款
select cust_name,d.cust_sum
from customer a,
(select cust_id,cust_sum
from (select cust_id, sum(tot_amt) as cust_sum
from sales
group by cust_id ) b
where b.cust_sum =
( select max(cust_sum)
from (select cust_id, sum(tot_amt) as cust_sum
from sales
group by cust_id ) c )
) d
where a.cust_id=d.cust_id
问题16、查找销售总额少于1000元的销售员编号、姓名和销售额
select emp_no,emp_name,d.sale_sum
from employee a,
(select sale_id,sale_sum
from (select sale_id, sum(tot_amt) as sale_sum
from sales
group by sale_id ) b
where b.sale_sum <1000
) d
where a.emp_no=d.sale_id
问题17、查找至少销售了3种商品的客户编号、客户名称、商品编号、商品名称、数量和金额
select a.cust_id,cust_name,b.prod_id,prod_name,d.qty,d.qty*d.unit_price
from customer a, product b, sales c, sale_item d
where a.cust_id=c.cust_id and d.prod_id=b.prod_id and
c.order_no=d.order_no and a.cust_id in (
select cust_id
from (select cust_id,count(distinct prod_id) prodid
from (select cust_id,prod_id
from sales e,sale_item f
where e.order_no=f.order_no) g
group by cust_id
having count(distinct prod_id)>=3) h )
问题18、查找至少与世界技术开发公司销售相同的客户编号、名称和商品编号、商品名称、数量和金额
select a.cust_id,cust_name,d.prod_id,prod_name,qty,qty*unit_price
from customer a, product b, sales c, sale_item d
where a.cust_id=c.cust_id and d.prod_id=b.prod_id and
c.order_no=d.order_no and not exists
(select f.*
from customer x ,sales e, sale_item f
where cust_name='世界技术开发公司' and x.cust_id=e.cust_id and
e.order_no=f.order_no and not exists
( select g.*
from sale_item g, sales h
where g.prod_id = f.prod_id and g.order_no=h.order_no and
h.cust_id=a.cust_id)
)
问题19、查找表中所有姓刘的职工的工号，部门，薪水
select emp_no,emp_name,dept,salary
from employee
where emp_name like '刘%'
问题20、查找所有定单金额高于20000的所有客户编号
select cust_id
from sales
where tot_amt>20000
问题21、统计表中员工的薪水在40000-60000之间的人数
select count(*)as 人数
from employee
where salary between 40000 and 60000
问题22、查询表中的同一部门的职工的平均工资，但只查询＂住址＂是＂上海市＂的员工
select avg(salary) avg_sal,dept
from employee
where addr like '上海市%'
group by dept
问题23、将表中住址为"上海市"的员工住址改为"北京市"
update employee
set addr like '北京市'
where addr like '上海市'
问题24、查找业务部或会计部的女员工的基本信息
select emp_no,emp_name,dept
from employee
where sex='F'and dept in ('业务','会计')
问题25、显示每种产品的销售金额总和，并依销售金额由大到小输出
select prod_id ,sum(qty*unit_price)
from sale_item
group by prod_id
order by sum(qty*unit_price) desc
问题26、选取编号界于‘C0001’和‘C0004’的客户编号、客户名称、客户地址。
select CUST_ID,cust_name,addr
from customer
where cust_id between 'C0001' AND 'C0004'
问题27、计算出一共销售了几种产品
select count(distinct prod_id) as '共销售产品数'
from sale_item
问题28、将业务部员工的薪水上调3%
update employee
set salary=salary*1.03
where dept='业务'
问题29、由employee表中查找出薪水最低的员工信息
select *
from employee
where salary=
(select min(salary )
from employee )
问题30、使用join查询客户姓名为"客户丙"所购货物的"客户名称","定单金额","定货日期","电话号码"
select a.cust_id,b.tot_amt,b.order_date,a.tel_no
from customer a join sales b
on a.cust_id=b.cust_id and cust_name like '客户丙'
问题31、由sales表中查找出订单金额大于“E0013业务员在1996/10/15这天所接每一张订单的金额”的所有订单
select *
from sales
where tot_amt>all
(select tot_amt
from sales
where sale_id='E0013'and order_date='1996/10/15')
order by tot_amt
问题32、计算'P0001'产品的平均销售单价
select avg(unit_price)
from sale_item
where prod_id='P0001'
问题33、找出公司女员工所接的定单
select sale_id,tot_amt
from sales
where sale_id in
(select sale_id from employee
where sex='F')
问题34、找出同一天进入公司服务的员工
select a.emp_no,a.emp_name,a.date_hired
from employee a
join employee b
on (a.emp_no!=b.emp_no and a.date_hired=b.date_hired)
order by a.date_hired
问题35、找出目前业绩超过232000元的员工编号和姓名
select emp_no,emp_name
from employee
where emp_no in
(select sale_id
from sales
group by sale_id
having sum(tot_amt)<232000)
问题36、查询出employee表中所有女职工的平均工资和住址在＂上海市＂的所有女职工的平均工资
select avg(salary)
from employee
where sex like 'f'
union
select avg(salary)
from employee
where sex like 'f' and addr like '上海市%'
问题37、在employee表中查询薪水超过员工平均薪水的员工信息
Select * from employee where salary>(select avg(salary) from employee)
问题38、找出目前销售业绩超过40000元的业务员编号及销售业绩，并按销售业绩从大到小排序
Select sale_id ,sum(tot_amt)
from sales
group by sale_id
having sum(tot_amt)>40000
order by sum(tot_amt) desc
问题39、找出公司男业务员所接且订单金额超过2000元的订单号及订单金额
Select order_no,tot_amt
From sales ,employee
Where sale_id=emp_no and sex='M' and tot_amt>2000
问题40、查询sales表中订单金额最高的订单号及订单金额
Select order_no,tot_amt from sales where tot_amt=(select max(tot_amt) from sales)
问题41、查询在每张订单中订购金额超过24000元的客户名及其地址
Select cust_name,addr from customer a,sales b where a.cust_id=b.cust_id and tot_amt>24000
问题42、求出每位客户的总订购金额，显示出客户号及总订购金额，并按总订购金额降序排列
Select cust_id,sum(tot_amt) from sales
Group by cust_id
Order by sum(tot_amt) desc
问题43、求每位客户订购的每种产品的总数量及平均单价，并按客户号，产品号从小到大排列
Select cust_id,prod_id,sum(qty),sum(qty*unit_price)/sum(qty)
From sales a, sale_item b
Where a.order_no=b.order_no
Group by cust_id,prod_id
Order by cust_id,prod_id
问题44、查询订购了三种以上产品的订单号
Select order_no from sale_item
Group by order_no
Having count(*)>3
问题45、查询订购的产品至少包含了订单10003中所订购产品的订单
Select distinct order_no
From sale_item a
Where order_no<>'10003'and not exists (
Select * from sale_item b where order_no ='10003' and not exists
(select * from sale_item c where c.order_no=a.order_no and c.prod_id=b.prod_id))
问题46、在sales表中查找出订单金额大于“E0013业务员在1996/11/10这天所接每一张订单的金额”的所有订单，并显示承接这些订单的业务员和该订单的金额
Select sale_id,tot_amt
from sales
where tot_amt>all(select tot_amt from sales where sale_id='E0013' and order_date='1996/11/10')
问题47、查询末承接业务的员工的信息
Select *
From employee a
Where not exists
(select * from sales b where a.emp_no=b.sale_id)
问题48、查询来自上海市的客户的姓名，电话、订单号及订单金额
Select cust_name,tel_no,order_no,tot_amt
From customer a ,sales b
Where a.cust_id=b.cust_id and addr='上海市'
问题49、查询每位业务员各个月的业绩，并按业务员编号、月份降序排序
Select sale_id,month(order_date), sum(tot_amt)
from sales
group by sale_id,month(order_date)
order by sale_id,month(order_date) desc
问题50、求每种产品的总销售数量及总销售金额，要求显示出产品编号、产品名称，总数量及总金额，并按产品号从小到大排列
Select a.prod_id,prod_name,sum(qty),sum(qty*unit_price)
From sale_item a,product b
Where a.prod_id=b.prod_id
Group by a.prod_id,prod_name
Order by a.prod_id
问题51、查询总订购金额超过’C0002’客户的总订购金额的客户号，客户名及其住址
Select cust_id, cust_name,addr
From customer
Where cust_id in (select cust_id from sales
Group by cust_id
Having sum(tot_amt)>
(Select sum(tot_amt) from sales where cust_id='C0002'))
问题52、查询业绩最好的的业务员号、业务员名及其总销售金额
select emp_no,emp_name,sum(tot_amt)
from employee a,sales b
where a.emp_no=b.sale_id
group by emp_no,emp_name
having sum(tot_amt)=
(select max(totamt)
from (select sale_id,sum(tot_amt) totamt
from sales
group by sale_id) c)
问题53、查询每位客户所订购的每种产品的详细清单，要求显示出客户号，客户名，产品号，产品名，数量及单价
select a.cust_id, cust_name,c.prod_id,prod_name,qty, unit_price
from customer a,sales b, sale_item c ,product d
where a.cust_id=b.cust_id and b.order_no=c.order_no and c.prod_id=d.prod_id
问题54、求各部门的平均薪水，要求按平均薪水从小到大排序
select dept,avg(salary) from employee group by dept order by avg(salary)
