ExamOfficeLabel
  user UserId
  name ExamOfficeLabelName
  status MessageStatus
  priority Int          -- determines label ordering
  UniqueExamOfficeLabel user name
  deriving Generic

ExamOfficeExamLabel
  exam ExamId
  label ExamOfficeLabelId
  UniqueExamOfficeExamLabel exam
  deriving Generic
ExamOfficeExternalExamLabel
  externalExam ExternalExamId
  label ExamOfficeLabelId
  UniqueExamOfficeExternalExamLabel externalExam
  deriving Generic