创建数据库
create database school
on
(
name=school_data,
filename='E:\mydata\school_data.mdf',
size=10,
maxsize=50,
filegrowth=5
),
(
name=school_data3,
filename='E:\mydata\school_data3.ndf',
size=10,
maxsize=50,
filegrowth=5
)
log on
(name=school_log,
filename='E:\mydata\school_log.ldf',
size=5,
maxsize=100,
filegrowth=5
)
增加次要数据库文件
alter database school
add file
(
name=school_data2,filename='E:\mydata\school_data2.ndf',
size=5,
maxsize=100,
filegrowth=5
)
删除次要数据库文件
alter database school
remove file school_data2
删除数据库
drop database school
建立表格
use school
create table Student
(
sno int primary key identity(201701,1),
sname Varchar(10),
sage int not null,
sdept Varchar(30) not null
)
create table Course
(
cno Varchar(30),
cname Varchar(30),
cbefore Varchar(15)
constraint PK_cname primary key(cname)
)
create table SC
(
sno int,
cno Varchar(30),
grade int not null check(grade >=0 and grade <=100),
cname Varchar(30)
constraint PK_s_c primary key(sno,cno)
constraint FK_cname foreign key references Course(cname) on update cascade not null
)
新增列
alter table Student
add sex varchar(20) default '男'
改变长度
alter table Student
alter column sname varchar(8)
删除表
drop table Student
drop table Course
drop table SC
查询表
select *
from Student
select *
from Course
select *
from SC
删除列
alter table Course
drop column cbefore