请教SQL SERVER基础语句！

---创建表，且每个字段不能为空
create table Student_info
(
id int identity primary key,
name varchar(20) not null,
address varchar(200) not null,
age int not null,
department varchar(50) not null
);
go;--批处理语句
----插入数据
insert into Student_info values('张三','北京',20,'软件');
insert into Student_info values('李四,'上海,22,'软件);
insert into Student_info values('王五,'深圳,30,'网络');
go;
----查询语句
select max(age) age,name,department,address from student_info group by department

create table person(
id int,
name varchar2(20),
address varchar2(50),
age int,
department varchar2(25)
);

insert into person values(1,'张三',20,'软件');
insert into person values(2,'李四',22,'软件');
insert into person values(3,'王五',30,'网络');

select * from (select * from person order by age dec) maxage where maxage.id = 1;

1、建表
USE [LianXi]
GO

/****** Object: Table [dbo].[StafferTab] Script Date: 03/14/2011 20:13:47 ******/
SET ANSI_NULLS ON
GO

SET QUOTED_IDENTIFIER ON
GO

SET ANSI_PADDING ON
GO

CREATE TABLE [dbo].[StafferTab](
[Id] [int] NOT NULL,
[Name] [varchar](50) NULL,
[Address] [varchar](50) NULL,
[Age] [int] NULL,
[Department] [varchar](50) NULL,
CONSTRAINT [PK_StafferTab] PRIMARY KEY CLUSTERED
(
[Id] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]

GO

SET ANSI_PADDING OFF
GO

2、插入数据
INSERT INTO [LianXi].[dbo].[StafferTab]([Id],[Name],[Address],[Age],[Department])
VALUES (1,'张三','北京',20,'软件')
GO
INSERT INTO [LianXi].[dbo].[StafferTab]([Id],[Name],[Address],[Age],[Department])
VALUES (2,'李四','上海',22,'软件')
GO
INSERT INTO [LianXi].[dbo].[StafferTab]([Id],[Name],[Address],[Age],[Department])
VALUES (3,'王五','深圳',30,'网络')
GO

3最大
select max(age),department,Name
from StafferTab
group by department,Name