Django在两个字段上组合过滤器

Question

我对 Django 比较陌生。我在过滤数据时遇到问题。我有两个模型，如下所示:

Account(models.Model):
    name = models.CharField(max_length=60)
    hotel = models.ForeignKey(Hotel)
    account_type = models.CharField(choices=ACCOUNT_TYPE, max_length=30)

Transaction(models.Model):        
    account = models.ForeignKey(Account, related_name='transaction')
    transaction_type = models.CharField(choices=TRANSACTION_TYPE, max_length=15)
    description = models.CharField(max_length=100, blank=True, null=True)
    date_created = models.DateTimeField(default=timezone.now)

ACCOUT_TYPE 是:

ACCOUNT_TYPE = (
  (0, 'Asset'),
  (1, 'Liabilities'),
  (2, 'Equity'),
  (3, 'Income'),
  (4, 'Expense')
)

我想过滤账户类型为 Income的所有交易和 Expense在给定的日期范围内。如何在 Django 中组合这些过滤器？

我试过这样:

income_account = Account.objects.filter(account_type=3)
expense_account = Account.objects.filter(account_type=4)
transactions = Transaction.objects.filter(Q(
  account=income_account,
  date_created__gte=request.data['start_date'],
  date_created__lte=request.data['end_date']
) & Q(
  account=expense_account,
date_created__gte=request.data['start_date'],
date_created__lte=request.data['end_date'])).order_by('date_created')

但它不起作用。它引发以下错误:

  ProgrammingError: more than one row returned by a subquery used as an expression

Answer 1

income_account和 expense_account不是单个对象，它是一个对象列表。所以，而不是这个 account=income_account而这个 account=expense_account尝试使用 in :account__in=income_account和 account__in=expense_account .
你也可以像这样简化查询集:

accounts = Account.objects.filter(Q(account_type=3) | Q(account_type=4))
transactions = Transaction.objects.filter(
    account__in=accounts,
    date_created__gte=request.data['start_date'],
    date_created__lte=request.data['end_date']
).order_by('date_created')