What are complete recovery and incomplete recovery in Oracle

In Oracle, complete recovery means that when the data file fails due to media failure, use the os command to copy the data file backup and restore it to the latest time point before the failure; incomplete recovery means that when the database fails due to media failure or user error, During operation, use backed up data, archived log files, etc. to restore the database to a time point before the latest time point before the failure.

The operating environment of this tutorial: Windows 10 system, Oracle 11g version, Dell G3 computer.

What are full recovery and incomplete recovery in Oracle

Full recovery: Use redo logs or incremental backups to restore data blocks to the time closest to the current time point. It is called a full recovery because Oracle applies all modifications in the archive logs and online redo logs.

When a media failure occurs in a data file, use the os command to copy the data file backup, and use the SQL recovery command to apply archive logs and redo logs, and finally restore the data file to the state of the failure point. That is, restore to the most recent point in time before the failure.

Incomplete recovery: Use backup to generate a non-current version of the database. In other words, all redo logs generated after the backup will not be used during the recovery process

When a media failure or user misoperation occurs in the database, the backed up data files, archive log files and redo logs will be used Restore the database to its state at a time between the backup point and the point of failure. That is, restore to a time point before the most recent time point before the failure.

Incomplete recovery of the entire database is usually generated under the following circumstances

1: Media failure damaged several or all online redo log files;

2: User Data loss caused by operations, for example, the user accidentally deleted a table;

3: Complete recovery cannot be performed due to the loss of individual archive log files;

4: Loss of current control file, the database must be opened using the backed up control file.

In order to perform incomplete media recovery, the data files must be restored using backups before the recovery time point

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