SQL语言操作数据表

---检查数据库是否存在 use master go if exists(select * from sysdatabases where) drop database studentdb ----创建数据库 Create database studentdb on primary ( name='sudent', filename='d:\data\student.mdf', size=10, maxsize=50, filegrowth=3

---检查数据库是否存在

use master

go

if exists(select * from sysdatabases where)

 drop database studentdb

----创建数据库

Create database studentdb

on primary (

 name='sudent',

 filename='d:\data\student.mdf',  

size=10,

maxsize=50,  

filegrowth=3

)

log on (

 name='student-log',

 filename='d:\data\student-log.ldf',

 size=15,

 filegrowth=15%

)

---创建第一张表

use studentdb

go

if exists (select * from sysobjects where)  

drop table t_student

create table t_student

(

 sno char(3) not null,  

sname char(20) null,  

sdenger char(2) not null,

 sbirth datetime null,

 sclass varchar(20) not null

)

---创建第二张表

use studentdb

go

if exists (select * from sysobjects where)  

drop table t_course

create table t_course

( 

 cno char(3) not null,

 cname char(20) null  

)

--创建第三张表

use studentdb go

if exists (select * from sysobjects where)

 drop table t_score

create table t_score

(

 sno char(3) not null,

 cno char(3) not null,

 score int not null  

)

--修改列

alter table t_student

alter column sno char(12)

--增加列

alter table t_student

add sfavorate char(30)

--删除列

alter table t_student

drop column sfavorate

--查看表

sp_help t_student

--删除表

drop table t_student