computed field <str> in relation <str> not imported

  Explanation:  You specified a computed field in your database
  that could not be imported.  Perhaps the field references other
  fields and relations that were deleted from the database by an
  older version of the software that would have permitted such a
  thing.

  User Action:  You must investigate the problem further.  The
  table should have been properly imported except for the listed
  column.