ORACLE增量備份

標籤：

Incremental Backup: 2 個層級,level 0 和level 1, 0 級備份包含資料檔案中所有block,1 級備份改變的block,執行增量備份的時候,要先做0 級備份,作為增量備份的基礎.
(1)An INCREMENTAL backup at level 0 backs up all data blocks in datafiles being backed up.
(2)A level 1 backup copies only changed blocks. A level 1 incremental backup is either differential or CUMULATIVE. If cumulative, RMAN backs up all blocks changed since the most recent level 0 backup. If differential, RMAN backs up blocks updated since the most recent level 0 or level 1 incremental backup.

A backup strategy as follows:
1. On Sunday, an incremental level 0 tape backup is performed
2. Monday through Saturday, a cumulative incremental level 1 tape backup is performed

A. The backup performed in step 1 backs up all blocks that have ever been in use in the database
B. The backup performed in step 2 copies all the blocks changed since the most recent level 0 backup

增量備份分2 類:
差異增量:包含上次增量備份以來更改的所有塊,預設增量備份方式;
累積增量:包含上次層級為0 的增量備份以來更改的所有塊.

 

ORACLE增量備份