Question

我有两种模式：

class AuthUser(models.Model):
    id = models.IntegerField(primary_key=True) 
    password = models.CharField(max_length=128)
    last_login = models.DateTimeField(blank=True, null=True)
    is_superuser = models.BooleanField()
    first_name = models.CharField(max_length=30)
    last_name = models.CharField(max_length=30)
    email = models.CharField(max_length=254)
    is_staff = models.BooleanField()
    is_active = models.BooleanField()
    date_joined = models.DateTimeField()
    username = models.CharField(unique=True, max_length=30)

    class Meta:
        managed = False
        db_table = 'auth_user'

class SocialAuthUsersocialauth(models.Model):
    id = models.IntegerField(primary_key=True)  # AutoField?
    provider = models.CharField(max_length=32)
    uid = models.CharField(max_length=255)
    user = models.ForeignKey(AuthUser, models.DO_NOTHING)
    extra_data = models.TextField()

    class Meta:
        managed = False
        db_table = 'social_auth_usersocialauth'
        unique_together = (('provider', 'uid'),)

我需要在它们之间创建类似SQL JOIN的东西，并在queryset中存储连接表。

我试着这样做：

def namedtuplefetchall(cursor):
    desc = cursor.description
    nt_result = namedtuple('Result', [col[0] for col in desc])
    return [nt_result(*row) for row in cursor.fetchall()]

def examp(request):
    context = dict()
    cursor = connection.cursor()
    cursor.execute("""
    SELECT *
    FROM auth_user
    JOIN social_auth_usersocialauth
    ON auth_user.id = social_auth_usersocialauth.user_id
    """)
    context['usersauth'] = namedtuplefetchall(cursor)
    return render(request, 'try.html', context)

但我有例外遇到重复的字段名称：＆＃39; id＆＃39;，我不知道如何处理。

Answer 1

应将rename = True属性添加到namedtuple调用

namedtuple('Result', [col[0] for col in desc], rename=True)

Answer 2

出于这些目的，您应该使用select_related和prefetch_related 如果您想从相关模型中获取表格，请使用“select_related＆＃39;：

”

SocialAuthUsersocialauth.objects.select_related('user')

如果要获取所有相关表格，请使用＆＃39; prefetch_related＆＃39;：

AuthUser.objects.prefetch_relatd('socialauthusersocialauth_set')

它将向您的查询集添加其他属性，其名称为相关字段。还可以在related_name中更好地添加属性ForeignKey，以便更明确地使用。

django查询集的两个模型

2 个答案: