ORA-01150: cannot prevent writes - file string has online backup set

admin

ORA-01150: cannot prevent writes - file string has online backup set
Cause: An attempt to make a tablespace read only or offline normal found that an
online backup is still in progress. It will be necessary to write the file header to end
the backup, but that would not be allowed if this command succeeded.
Action: End the backup of the offending tablespace and retry this command.