Question

class Investor(Model):
    name = CharField(max_length=16)

class Project(Model):
    plan_finance = IntegerField()

class ProjectProcess(Model):
    project = OneToOneField('Project')
    investors = ManyToManyField('Investor')

class InvestShip(Model):
    project = ForeignKey('Project')
    investor = ForeignKey('Investor')
    invest_amount = IntegerField()

如何找到已经 已完成资助的项目 ，换句话说，从投资者那里收到的钱＆＃39; ＆GT; plan_finance

Answer 1

您可以在相关集上使用annotation，然后对其进行过滤。

from django.db.models import Sum

Project.objects.annotate(invested_sum=Sum('investship_set__invest_amount')).filter(invested_sum__gte=plan_finance)

如何将相关的Sum与值本身进行比较

1 个答案: