python - 抛出 ZeroDivisionError

Question

我需要对一些数据进行计算，所以在注释中我将一些数学逻辑与其他字段放在一起，但只要有 0，它就会抛出错误。我需要在注释中处理该错误。我的代码如下所示:

total_amount = Invoice.objects.filter(client_account__account_UID=account_UID,
                                              created_at__range=(from_date, to_date)
                                              ).aggregate(Sum('total_amount'))['total_amount__sum']

total_billable_leads = CampaignContact.objects.filter(campaign=campaigns, billable=True, billable_item__created_at__range=(from_date, to_date)).count()

cch = CampaignContactHistory.objects.annotate(
            campaign_name=F('campaign__name')
                 ).values('campaign_name'
                 ).filter(id__in=cch_ids
                 ).annotate(
            total=Count('lead_status'),
            scheduled=Count(Case(When(lead_status='10', then=1))),
            total_billable=(int(total_amount) / total_billable_leads) * Count(Case(When(campaign_contact__billable=True, then=1))),
        )

在 total_billable 中，有一个 total_billable_leads 变量，它可能有零(0)然后在除法上它会抛出错误。所以，请帮我在注释中处理这个异常。

CampaignContactHistory 模型

class CampaignContactHistory(DateAwareModel):
    campaign_contact = models.ForeignKey(CampaignContact, on_delete=models.CASCADE)
    lead_status = models.CharField(max_length=20, choices=leadstatus, default=FRESH)
    campaigner = models.ForeignKey(Resource, on_delete=models.CASCADE)
    response_date = models.DateTimeField(null=True, blank=True)
    first_reponse = models.TextField(blank=True, null=True, default='')
    second_reponse = models.TextField(blank=True, null=True, default='')
    campaign = models.ForeignKey(Campaign, null=True, blank=True)

对于我想要的结果，如果它是错误或零(0)，它应该返回零(0)，否则返回计算值。

Answer 1

total_amount 和 total_billable_leads 是常量，所以你会在 python 级别得到错误，所以解决方案是:

if total_billable_leads:
    total_amount_avg = int(total_amount) / total_billable_leads
else:
    total_amount_avg = 0

cch = CampaignContactHistory.objects.annotate(
            campaign_name=F('campaign__name')
                 ).values('campaign_name'
                 ).filter(id__in=cch_ids
                 ).annotate(
            total=Count('lead_status'),
            scheduled=Count(Case(When(lead_status='10', then=1))),
            total_billable=total_amount_avg * Count(Case(When(campaign_contact__billable=True, then=1))),
            #               ^^^^^^^^^^^^^^^
        )