Question

想法是Requisition可以有多行，这就是为什么我在unique_together和parent_req上加入了sequence约束的原因。

每行都有一个与之关联的状态。我为每个状态添加了1到5的评分，但可能会有某些状态的评分相同。我的想法是，我想保存所有行中评分最高的状态，并将其传递给模板。我尝试使用.annotate来获得最高评分，但是我无法获取与该评分相关的实际状态字段。如果某个评分存在多个状态，那么它应该抢先看到它。

示例：

**Status** | **Rating**
status1    |     1
status2    |     2
status3    |     3
status4    |     3
status5    |     4
status6    |     5

models.py

class Requisition(models.Model):
    username = models.ForeignKey(
        'users.CustomUser',
        on_delete=models.CASCADE,
        related_name='req_user')
    signature = models.CharField(
        max_length=10,
        blank=True,
        null=True)

class RequisitionLine(models.Model):
    parent_req = models.ForeignKey(
        'Requisition',
        on_delete=models.CASCADE,
        related_name='par_req_line')
    sequence = models.PositiveIntegerField()
    status = models.ForeignKey(
        'RequisitionStatus',
        related_name='req_status',
        on_delete=models.CASCADE,
        blank=True,
        null=True)

    class Meta:
        unique_together = ('parent_req','sequence')

class RequisitionStatus(models.Model):
    status = models.CharField(
        max_length=20)
    rating = models.SmallIntegerField()

    def __str__(self):
        return self.status

views.py

def pending_action(request):
    requisition_status = [
        'All', 'Created', 'For Assistance', 'Assistance Complete', 'Assistance Rejected',
    ]
    FA_status = RequisitionStatus.objects.get(status='For Assistance')

    current_status = 'All'
    status_list = []

    all_status = RequisitionStatus.objects.all()
    status_list = [status.status for status in all_status]

    if request.GET.get('Filter') in status_list:
        user_req_lines_incomplete = RequisitionLine.objects.filter(
            Q(parent_req__username=request.user)
            & Q(status__status=request.GET.get('Filter')))
        current_status = request.GET.get('Filter')
    else:
        user_req_lines_incomplete = RequisitionLine.objects.filter(
            parent_req__username=request.user) \
            .exclude(status__status='Completed')

    # This is where I query for the status and right now im grabbing the actual rating.
    # I want to be able to access the status like I am accessing the aggregated price
    user_reqs = Requisition.objects.filter(
        par_req_line__in=user_req_lines_incomplete) \
        .annotate(
            aggregated_price=Sum('par_req_line__total_price'),
            header_status=Max('par_req_line__status__rating'))

    return render(
        request,
        'req/pending_action.html',
        {
            'user_reqs': user_reqs,
            'user_req_lines_incomplete': user_req_lines_incomplete,
            'requisition_status': requisition_status, 
            'current_status': current_status,
            'FA_status': FA_status,
        })

Django-使用Django ORM和相关管理器

0 个答案: