1.create database dataname 这是创建数据库最简单的方法.数据库的各个属性都是默认.如数据库文件与日志文件存储目录.数据库大小等. 下面介绍下常用决定数据库属性的子句. on:简单理解为定义存储数据库文件的位置,看下面代码. filename:数据库的逻辑
1.create database dataname
这是创建数据库最简单的方法.数据库的各个属性都是默认.如数据库文件与日志文件存储目录.数据库大小等.
下面介绍下常用决定数据库属性的子句.
- on:简单理解为定义存储数据库文件的位置,看下面代码.
- filename:数据库的逻辑别名
- size:数据库初始大小
- maxsize:数据库初大容量
- filegrowth:数据库每次增加的容量.
- log on:简单理解为定义存储数据库日志文件的位置.
看创建代码:
- create database Accounting
- on(name='AccountingName',
- filename='F:/总结/Sql/创建和修改数据表/Accounting.mbdf',
- size=10mb,
- maxsize=50mb,
- filegrowth=5mb)
- log on(name='AccountingLog',
- filename='F:/总结/Sql/创建和修改数据表/Accounting.log',
- size=10mb,
- maxsize=50mb,
- filegrowth=5mb)
上面说到了 filegrowth:数据库每次增加的容量 结合代码来说.就是初始数据库大小为10mb.当数据库容量要超出时.他会自动增加5mb.这会就是15mb大小.最大到50mb
create database song on
(name=ktvdata,filename='D:/database/ktvdata.mdf',
size=8MB,maxsize=9MB,filegrowth=100KB)
log on
(name=ktvdata_log,filename='D:/database/ktvdata.ldf',
size=9MB,maxsize=10MB,filegrowth=100KB)
go
2. 使用ALTER DATABASE语句修改数据库
例4-3 将两个数据文件和一个事务日志文件添加到test数据库中。
程序清单如下:
ALTER DATABASE Test
ADD FILE
(NAME = Test1, FILENAME='c:/Program Files/Microsoft SQL Server/MSSQL/Data/test1.ndf', SIZE =
5MB, MAXSIZE = 100MB, FILEGROWTH = 5MB),
(NAME = Test2, FILENAME='c:/Program Files/Microsoft SQL Server/MSSQL/Data/test2.ndf', SIZE =
3MB, MAXSIZE = 10MB, FILEGROWTH = 1MB)
GO
ALTER DATABASE Test
ADD LOG FILE ( NAME = testlog1, FILENAME='c:/Program Files/Microsoft SQL
Server/MSSQL/Data/testlog1.ldf', SIZE = 5MB, MAXSIZE = 100MB, FILEGROWTH = 5MB)
GO
3、重命名test为demo
sp_renamedb 'test','demo'
4. 删除数据库: drop database song
go

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