SQL--DDL

DDL (Data Discription Language) 数据库定义语言

basic object	operation
	Create	Alter	Drop
database	create database		drop database
table	create table	alter table	drop table
view	create view		drop view
index	create index		drop index

---

DataBase

create database Three_Kingdom
on primary (
name='Three_Kingdom_data',
filename='d:\Three_Kingdom.mdf',
size=3mb,
maxsize=100mb,
filegrowth=2%

)
log on(
name='Three_Kingdom_ldf',
filename='d:\Three_Kingdom.ldf',
size=1mb,
maxsize=50mb,
filegrowth=2
)

/*drop database*/
drop database Three_Kingdom

 

 primary：指定主文件组中的文件。

 log on：指明事务日志文件的明确定义。

 name：指定数据库的逻辑名称

 filename ：指定数据库文件.mdf或.ndf的名称和路径。

 size：数据库初始容量。

 maxsize：数据库最大容量。

 filegrowth：指定文件每次增加容量的大小，当指定为0时，表示文件不增长。可以按百分比增长、数值增长。

---

Table

use Three_Kingdom
create table sanguo(
id smallint identity(1,1),
[number] nvarchar(5) not null, 
[name] nvarchar(10) not null,
[address] nvarchar (20) default'地址不详',
email nvarchar(20) check(email like'%@%'),
country nchar(1) check(country like'[魏蜀吴]')
primary key(number),
constraint cons_num check(number like'[0-9][0-9][0-9]')
)

drop table sanguo

alter table sanguo add
age int not null,
salary decimal(6,2) default 3200,
constraint cons_age check (age>20)

alter table sanguo 
drop constraint cons_age,column age

 View

create view V_Profile as
select [sanguo].[number],[sanguo].[name],[sanguo2].[zi]
from [sanguo],[sanguo2]
where[sanguo].[number]=[sanguo2].[number]


drop view V_profile

Index

create nonclustered index name_index
on sanguo([name])

drop  index [sanguo].name_index