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HomeDatabaseMysql Tutorial第四章 数据查询1(上机)

第四章 数据查询1(上机)

Jun 07, 2016 pm 03:22 PM
createdatabasedata queryInquireChapter Four

第四章 数据库查询(1) ==================================================================================== --创建数据库 create database dbSales go --使用数据库dbSales use dbSales go --创建职员表 create table tbEmp ( eID smallintidentity p

第四章 数据库查询(1)

====================================================================================

--创建数据库

create database dbSales
go
--使用数据库dbSales
use dbSales
go
--创建职员表
create table tbEmp
(
eID smallintidentity primary key,--职员编号
eName varchar(20)not null, --职员姓名
eSex varchar(2)not null --职员性别
check(esex in ('男','女')),
eAge smallintnot null check(eage>=18),--职员年龄
eAddr varchar(50)not null, --职员地址
eTel varchar(30)not null, --职员电话
eEmail varchar(30)null, --职员邮箱
eJoinTime datetimenot null, --入职时间
)
go
insert into tbemp---------------------------------------------------------
(ename,esex,eage,eaddr,etel,eemail,ejointime)
values
('赵龙','男',25,'湖南省长沙市伍家岭江南苑9栋203号','0731-4230123','zl@163.net','2005-10-5')
insert into tbemp---------------------------------------------------------
(ename,esex,eage,eaddr,etel,eemail,ejointime)
values
('李云','女',23,'湖南省长沙市东风路东风新村21栋502号','0731-4145268','ly@163.net','2003-7-3')
insert into tbemp---------------------------------------------------------
(ename,esex,eage,eaddr,etel,eemail,ejointime)
values
('孙一成','男',24,'湖南省株洲市601厂宿舍15栋308号','0732-8342567','syc@163.net','2002-2-11')
insert into tbemp---------------------------------------------------------
(ename,esex,eage,eaddr,etel,eemail,ejointime)
values
('林笑','男',27,'湖南省郴洲市人民医院20栋301号','0735-2245214','lx@163.net','2006-1-5')
insert into tbemp---------------------------------------------------------
(ename,esex,eage,eaddr,etel,eemail,ejointime)
values
('卫晴','女',23,'湖南省长沙市望月湖12栋403号','0731-8325124','wq@163.net','2007-3-5')



====================================================================================
--查询所有职员信息
select *from tbEmp


--查询所有职员的姓名,电话,地址
select ename ,etel,eaddr from tbEmp


--查询所有女职员的详细信息
select *from tbemp where esex='女'


--查询年龄在24到26岁之间的职员的姓名,性别
select ename,esex from tbemp where eage between 24 and 26


--查询家住长沙的女职员的姓名,电话,地址
select ename,etel,eaddr from tbemp where eaddr like '%长沙%'


--查询李云,孙一成,林笑的电话,地址
select ename,etel,eaddr from tbemp where ename='李云'or ename='孙一成'or ename='林笑'


--查询郴洲和株洲的职员的姓名,性别,年龄
select ename,esex,eage from tbemp where eaddr like '%郴洲%' or eaddr like '%株洲%'


--查询家住长沙,年龄在25到28岁之间的男职员的姓名
select ename from tbemp where eaddr like'%长沙%'and esex='男'and eage between 25 and 28


--查询邮件地址为空的职员
select ename from tbemp where eemail is null


--**查询入职时间超过两年的员工**
select ename from tbemp where datediff(yy,ejointime,getdate()) >2


--**查出1月份入职的员工**
select ename from tbemp where datepart(mm,ejointime)=1



--**将所有email为163.net的邮箱改为126.com **
update tbemp
set eemail= replace(eemail,'163.net','126.com')


--找出年龄最小的两位长沙员工
select top 2 ename,eage from tbemp where eaddr like '%长沙%' order by eage asc


--***查找员工信息,要求结果集表达方式为:
--字段名:个人信息
--内容描述:'员工1,赵龙,今年25岁,家住湖南省长沙市伍家岭江南苑9栋203号'
select '员工' + convert(char(2),eid) +','

+ ename + ', 今年' + convert(varchar(2),eage) + '岁, 家住' + eaddr as 个人信息 from tbemp


--**求所有员工的年龄总和
select sum(eage) '年龄总和' from tbemp


--***分别求男,女员工年龄总和

select sum(eage)年龄总和,esex 性别 from tbemp group by esex select sum(eage) from tbemp where esex='男' or esex='女'

====================================================================================

2013.12.02数据库第四次课


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