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DG提供了3种数据保护模式：最大保护（Maximum Protection）、最高性能（Maximum Performance）和最高可用（Maximum Availability），如下表所示：

表 3-32 DG三种模式的区别

数据库异地备份方案

在对数据库计划实施异地备份时，需要理解异地备份的目的。一般情况下有两种异地备份的需求：一是确保业务的实时以及最大程度减少由于单点故障导致业务中断；二是确保数据的安全，当生产节点出现物理故障时能通过异地备份及时的恢复数据。

 

    

  

  

  

 

  

 

  

  

 

  

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