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oracle增量和全量的差別,ORACLE全備份和0級增量備份的差別

比較官方的說法

Full

A backup of a datafile that includes every allocated block in the file being backed up. A full backup of a datafile can be an image copy, in which case every data block is backed up. It can also be stored in a backup set, in which case datafile blocks not in use may be skipped, according to rules in Oracle Database Backup and Recovery Reference.

A full backup cannot be part of an incremental backup strategy; that is, it cannot be the parent for a subsequent incremental backup.

Incremental

An incremental backup is either a level 0 backup, which includes every block in the file except blocks compressed out because they have never been used, or a level 1 backup, which includes only those blocks that have been changed since the parent backup was taken.

A level 0 incremental backup is physically identical to a full backup. The only difference is that the level 0 backup is recorded as an incremental backup in the RMAN repository, so it can be used as the parent for a level 1 backup.

網上搜到的隻言片語

The only difference between a level 0 backup and a full backup is that a full backup is never included in an incremental strategy. If no level 0 backup exists when you run a level 1 or higher backup, RMAN makes a level 0 backup automatically to serve as the base.

增量備份0級與全備份都是全備份,但是增量備份0級使用rman備份的話就隻備份了used block,而全備份備份了used and unused block

總結一下,二者有兩個地方不同

1

全備份不能被用作1級增量備份的基礎

2

使用rman備份的時候,全備份備份了used and unused block,0級使用rman備份的話就隻備份了used block