--创建 MyCompany数据库
use master
execute sp_configure \'show advanced options\',1 --开启权限
reconfigure
execute sp_configure \'xp_cmdshell\',1
reconfigure
execute xp_cmdshell \'mkdir e:\作业数据库\'--自动创建文件夹
execute sp_configure \'xp_cmdshell\',0--关闭权限,先关
reconfigure
execute sp_configure \'show advanced options\',0 后关,一句话,先开后关
reconfigure
if exists(select * from sysdatabases where name=\'MyCompany\')
drop database MyCompany
go
create database MyCompany
on primary
(
name=\'MyCompany_data\',
size=3mb,
fileGrowth=10%,
Maxsize=100mb,
filename=\'e:\作业数据库\MyCompany_data.mdf\'
)
log on
(name=\'MyCompany_log\',
size=3mb,
fileGrowth=10%,
Maxsize=100mb,
filename=\'e:\作业数据库\MyCompany_log.ldf\'
)
--部门表 department
-- dId
-- dName
use MyCompany
if exists(select * from sysobjects where name=\'department\')
drop table department
go
create table department
(dId int not null primary key identity(1,1),
dName nvarchar(50) not null
)
--员工表 employee
-- eId
-- eName
-- eSex
-- eAge
-- eSalary
-- eDepId
-- eInTime 入职时间
if exists(select * from sysobjects where name=\'employee\')
drop table employee
go
create table employee
( eId int not null primary key identity(1,1),
eName nvarchar(50),
eSex char(2),
eAge int,
eSalary money,
eDepId int,
eInTime datetime
)
添加外键FK_employee_department_eDepId
alter table employee add constraint FK_employee_department_eDepId foreign key(eDepId) references department(dId) insert into department values (\'教学部\') insert into department values (\'业务部\') insert into department values (\'学工部\') insert into employee values (\'李定\',\'男\',28,5000,1,\'2014-8-8\') insert into employee values (\'张月月\',\'女\',28,5000,2,\'2013-8-8\') insert into employee values (\'李定山\',\'男\',18,3000,3,\'2014-8-1\') insert into employee values (\'张三\',\'男\',18,1800,3,\'2014-7-1\') insert into employee values (\'张三1\',\'女\',18,1800,3,\'2013-7-1\') insert into employee values (\'张三2\',\'女\',28,4800,2,\'2011-7-1\') --建库 建表 建约束 添加测试数据 更新 和删除 --1、查询所有员工 select * from employee --2、查询工资超过2000快钱的员工 select * from employee where eSalary>2000 --3、查询最新进来的5个员工 ---降序排序 select top 5 * from employee order by eInTime desc --4、查询员工的平均工资 select avg() from select avg(eSalary) as 平均工资 from employee --5、查询总共有多少员工 count select count(*) as 员工数 from employee --6、查询每个部门有多少员工 ---按部门分组 select eDepId,count(*) as from employee group by eDepId --7、查询每个部门的平均工资 select eDepId,avg(eSalary) from employee group by eDepId --8、查询每个部门男员工的平均工资 select eDepId,eSex,avg(eSalary) from employee where eSex=\'男\' group by eDepId,eSex --9、查询平均工资超过2000的那些部门 having 对分组之后的数据再进行筛选 select eDepId,avg(eSalary) from employee group by eDepId having avg(eSalary)>200 --10、查询员工工资（姓名，工资）的同时，同一结果集显示平均工资和最高工资 --select \' \'+姓名，工资 from 表 --union --select cast(平均工资 as varchar()),最高工资 from 表 select eName,eSalary from employee union all select \'平均工资\',avg(eSalary) from employee union all select \'最高工资\',max(eSalary) from employee --这个方式也行 select eName,eSalary from employee union all select convert(varchar(20),avg(eSalary)) ,max(eSalary) from employee --11、查询名字里包含\'定,月\'的这些员工，并对结果按照年龄排序 select * from employee where eName like\'%三%\' or eName like \'%定%\'order by eAge
----好吧没有做更新和删除
update 表名 set 字段=新赋值 where 字段=‘’
例如：把张三的名字改为逗碧
update employee set eName=\'逗碧\' where eName=\'张三\'
delete table 表名 ===等开除吧，后面加where 否则全删除 -
--删除数据时候 把自增长列的值还原成种子
truncate table 表名 -- 强迫症而已