      headline = models.CharField(max_length=100)
      pub_date = models.DateTimeField()
  
      # Add virtual relation to the ArticleTranslation model.
      translation = CurrentTranslation(ArticleTranslation, ['id'], ['article'])
  
      class Meta:
          index_together = [
              ["headline", "pub_date"],
          ]
 
</s> remove     reporter = models.ForeignKey(Reporter)
    response_to = models.ForeignKey('self', null=True)
 </s> add     reporter = models.ForeignKey(Reporter, models.CASCADE)
    response_to = models.ForeignKey('self', models.SET_NULL, null=True) </s> remove     reporter = models.ForeignKey(Reporter, null=True)
 </s> add     reporter = models.ForeignKey(Reporter, models.SET_NULL, null=True) </s> remove     reporter = models.ForeignKey(Reporter)
    reporter_proxy = models.ForeignKey(ReporterProxy, null=True,
                                       related_name='reporter_proxy')
 </s> add     reporter = models.ForeignKey(Reporter, models.CASCADE)
    reporter_proxy = models.ForeignKey(
        ReporterProxy,
        models.SET_NULL,
        null=True,
        related_name='reporter_proxy',
    ) </s> remove     article = models.ForeignKey(Article, related_name="comments")
 </s> add     article = models.ForeignKey(Article, models.CASCADE, related_name="comments") </s> remove     parent = models.OneToOneField(Place)
 </s> add     parent = models.OneToOneField(Place, models.CASCADE)
    translation = CurrentTranslation(ArticleTranslation, models.CASCADE, ['id'], ['article'])
      headline = models.CharField(max_length=100)
      pub_date = models.DateTimeField()
  
      # Add virtual relation to the ArticleTranslation model.
    translation = CurrentTranslation(ArticleTranslation, models.CASCADE, ['id'], ['article'])
  
      class Meta:
          index_together = [
              ["headline", "pub_date"],
          ]
keep keep keep keep replace keep keep keep keep keep
 Fixed #21127 -- Started deprecation toward requiring on_delete for ForeignKey/OneToOneField 
tests/indexes/models.py