ORA-01157 cannot identify/lock data file string - see DBWR trace fileCause: The background process was either unable to find one of the data files or failed to lock it because the file was already in use. The database will prohibit access to this file but other files will be unaffected. However, the first instance to open the database will need to access all online data files. The accompanying error from the operating system describes why the file could not be identified.Action: At the operating system level, make the file available to the database. Then either open the database or do an ALTER SYSTEM CHECK DATAFILES.
to lock it because the file was already in use. The database will prohibit access to this
file but other files will be unaffected. However, the first instance to open the database
will need to access all online data files. The accompanying error from the operating
system describes why the file could not be identified.Action: At the operating system level, make the file available to the database. Then
either open the database or do an ALTER SYSTEM CHECK DATAFILES.