Oracle : Ошибка ORA-00255

"error archiving log %s of thread %s, sequence # %s"
*Cause: An error occurred during archiving.
*Action: Check the accompanying message stack for more detailed

If the online log is corrupted,
then the log can be cleared using the UNARCHIVED option. This will
make any existing backups useless for recovery to any time after
the log was created, but will allow the database to generate redo.

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