Full Backups and Incremental Backups - wykład

Full Backups and Incremental Backups
A full backup of a data file includes all used blocks of the data file. A full backup can
be either an image copy or backup set.
An incremental backup copies only those blocks in a data file that change between
backups. A level 0 incremental backup, which copies all blocks in the data file, is used
as a starting point for an incremental backup strategy.
A level 1 incremental backup copies only images of blocks that have changed since
the previous level 0 or level 1 incremental backup. Level 1 backups can be cumulative,
in which case all blocks changed since the most recent level 0 backup are included, or
differential, in which case only blocks changed since the most recent level 0 or level 1
incremental backup are included.
Incremental backups at level 0 can be either backup sets or image copies, but
incremental backups at level 1 can only be backup sets.
A typical incremental strategy makes level 1 backups at regular intervals such as once
each day.
During recovery, RMAN will automatically apply both incremental backups and redo
logs as required, to recover the database to the exact point in time desired.
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