学习笔记-备份还原

一、备份还原的概念

1、  完整备份：完整备份因为需要备份的数据量大，所以需要在空闲时间进行，并且定期进行。

2、  日志备份：日志备份的数据量小，备份时间为上一次备份到本次本分期间的数据，每天都可以进行备份，或者每小时都可以进行备份，据所需备份。

3、  差异备份：只备份修改过的数据，与每小时进行的日志备份配合使用，效率更高。

 

二、备份设备

1、  在进行备份数据的保存时，需要输入的文件路径很长，并且每次都要输入，难免麻烦费事，所以我们先给文件路径取好别名，即备份设备，以便之后书写代码的方便。

2、 创建备份设备

 IF EXISTS    
    (SELECT 1 FROM sys.backup_devices AS BD WHERE BD.name = \'dp_EduBase_FullBackup\')
    EXEC sp_dropdevice \'dp_EduBase_FullBackup\';
EXEC sp_addumpdevice \'DISK\',\'dp_EduBase_FullBackup\',\'C:\EduBase\Backup\Full\dp_EduBase_FullBackup.bak\';    
IF EXISTS    
    (SELECT 1 FROM sys.backup_devices AS BD WHERE BD.name = \'dp_EduBase_DiffBackup\')
    EXEC sp_dropdevice \'dp_EduBase_DiffBackup\';
EXEC sp_addumpdevice \'DISK\',\'dp_EduBase_DiffBackup\',\'C:\EduBase\Backup\Diff\dp_EduBase_DiffBackup.bak\';    
IF EXISTS    
    (SELECT 1 FROM sys.backup_devices AS BD WHERE BD.name = \'dp_EduBase_LogBackup\')
    EXEC sp_dropdevice \'dp_EduBase_LogBackup\';
EXEC sp_addumpdevice \'DISK\',\'dp_EduBase_LogBackup\',\'C:\EduBase\Backup\Log\dp_EduBase_LogBackup.bak\';    

 

1、  做完整备份

 USE EduBase;        
DECLARE @FullBkDesc VARCHAR(MAX);        //申明备份设备
SELECT        
    @FullBkDesc = \'Weekly full backup for \'+DB_NAME()+\' at \'+DATENAME(YEAR,GETDATE())+\',week \'+DATENAME(WEEK,GETDATE())+\'.(\'+CONVERT(VARCHAR,GETDATE(),120)+\')\';    
BACKUP DATABASE EduBase        
    TO dp_EduBase_FullBackup    
    WITH     
        INIT //INIT操作可以初始化文件，即可以覆盖掉之前的备份，保留本次操作过后的备份
        ,Name = \'EduBase_FullBackup\'
        ,DESCRIPTION = @FullBkDesc;

2、 做日志备份

DECLARE @LogBkDesc VARCHAR(MAX);        
SELECT        
    @LogBkDesc = \'Hourly log backup for \'+DB_NAME()+\' at \'+DATENAME(YEAR,GETDATE())+\',week \'+DATENAME(WEEK,GETDATE())+\',day \'+CONVERT(VARCHAR,DATEPART(W,GETDATE())-1)+\',hour \'+CONVERT(VARCHAR,DATEPART(HOUR,GETDATE()))+\'.(\'+CONVERT(VARCHAR,GETDATE(),120)+\')\';    
BACKUP LOG EduBase        
    TO dp_EduBase_LogBackup    
    WITH    
        INIT
        ,Name = \'EduBase_LogBackup\' 
        ,DESCRIPTION = @LogBkDesc;

3、做差异备份

 DECLARE @DiffBkDesc VARCHAR(MAX);        
SELECT        
    @DiffBkDesc = \'Daily Differential backup for \'+DB_NAME()+\' at \'+DATENAME(YEAR,GETDATE())+\',week \'+DATENAME(WEEK,GETDATE())+\',day \'+CONVERT(VARCHAR,DATEPART(W,GETDATE())-1)+\'.(\'+CONVERT(VARCHAR,GETDATE(),120)+\')\';    
BACKUP DATABASE EduBase        
    TO dp_EduBase_DiffBackup    
    WITH     
        DIFFERENTIAL 
        ,INIT
        ,Name = \'EduBase_DiffBackup\'