如何比较两个互不相关的distict模型中字段中的值

Question

我有两个不同的模型，彼此之间没有关系，但继承自一个抽象模型，这两个模型有共同的电子邮件字段，我想检查一下这个模型中包含的电子邮件值是否存在于另一个模型中。这是我的模型。

class BaseRespondent(SafeDeleteModel):
    _safedelete_policy = SOFT_DELETE_CASCADE

    class Meta:
    abstract = True

    id = models.UUIDField(primary_key=True, default=uuid.uuid4,     editable=False)
    name = models.CharField(max_length=256)
    email = models.EmailField()
    pos_applied = models.ForeignKey(PositionApplied, on_delete=_safedelete_policy,
                                null=True)
    date = models.DateField(auto_now_add=True)
    test = models.ForeignKey(Test, on_delete=models.SET_NULL, null=True, blank=True)

class Respondent(BaseRespondent):
    least_disc = models.CharField(max_length=256, default='')
    most_disc = models.CharField(max_length=256, default='')
    most_personality = models.ForeignKey(Personality, on_delete=models.SET_NULL,
                                     null=True, related_name="most_personality")
    least_personality = models.ForeignKey(Personality, on_delete=models.SET_NULL,
                                      null=True, related_name="least_personality")
    # combine = GenericRelation(Combined_Respondent, related_query_name='disc')

    def result(self):
        return format_html(
        '<a href="{0}result/{1}">View result</a>',
        settings.SITE_URL,
        self.id,
    )


    class Meta:

        verbose_name = "DISC Respondent"
        verbose_name_plural = "DISC Respondents"

class MBTIRespondent(BaseRespondent):
    first_col_component = models.CharField(max_length=32, null=True)
    first_col_score = models.CharField(max_length=32, null=True)

    third_col_component = models.CharField(max_length=32, null=True)
    third_col_score = models.CharField(max_length=32, null=True)

    fifth_col_component = models.CharField(max_length=32, null=True)
    fifth_col_score = models.CharField(max_length=32, null=True)

    seventh_col_component = models.CharField(max_length=32, null=True)
    seventh_col_score = models.CharField(max_length=32, null=True)

    personality = models.ForeignKey(MbtiPersonality, on_delete=models.SET_NULL,
                                null=True)
    # combine = GenericRelation(Combined_Respondent, related_query_name='mbti')

    def result(self):
        return format_html(
        '<a href="{0}result/mbti/{1}">View result</a>',
        settings.SITE_URL,
        self.id,
    )


    class Meta:

        verbose_name = "MBTI Respondent"
        verbose_name_plural = "MBTI Respondents"

我希望能够仅显示在答复者和MBTIRespondent中都存在的类似电子邮件

Answer 1

如果您想通过MBTIRespondent中的电子邮件获得所有应答者，您可以执行以下操作：

mtb_emails = MBTIRespondent.objects.values_list('email', flat=True)
respondent_with_mtb_emails = Respondent.objects.filter(email__in=mtb_emails)

另一种方法是连接这两个表，但您必须使用connection.cursor()编写一个原始查询。

cursor = connection.cursor().
cursor.execute('''SELECT * from %s as r inner join %s as mr on r.email=mr.email''' % (Respondent._meta.db_table, MBTIRespondent._meta.db_table))
rows = cursor.fetchall()