ORA-01124: cannot recover data file string - file is in use or recovery

Oracle error

ORA-01124: cannot recover data file string - file is in use or recovery

Cause: An attempt to do media recovery found that the file was not available for recovery. Either it is online and the database is open in some instance, or another process is curently doing media recovery on the file.

Action: Do not do media recovery.

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ORA-01123: cannot start online backup; media recovery not enabled

Oracle error

ORA-01123: cannot start online backup; media recovery not enabled

Cause: An attempt to start backup of an on-line tablespace failed because media recovery is not enabled.

Action: Enable media recovery and retry this operation.

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ORA-01122: database file string failed verification check

Oracle error

ORA-01122: database file string failed verification check

Cause: The information in this file is inconsistent with information from the control file. See accompanying message for reason.

Action: Make certain that the db files and control files are the correct files for this database.

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