ORA-19573: cannot obtain string enqueue for datafile string
Cause: The file access enqueue could not be obtained for a file specified in a backup, copy or restore operation. If the enqueue type shown is 'shared', then the file is the input file for a backup or copy. If the type is 'exclusive', then the file is the output file for a datafile copy or restore which is attempting to overwrite the currently active version of that file - in this case, the file must be offline or the database must be closed. If the type is 'read-only', then you are attempting to back up or copy this file while the database is in NOARCHIVELOG mode
Action: Wait until the conflicting operation is complete, then retry the copy or backup. If the database is in NOARCHIVELOG mode, then all files being backed up must be closed cleanly
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