Question

models.py

class SinglePoint(models.Model):
    attributes = models.TextField(blank=True)
    name = models.CharField(max_length=100)
    geom = models.PointField() #Kartenposition
    objects = models.GeoManager()

class Connection(models.Model):
    name = models.CharField(max_length=100)
    #points = models.ManyToManyField(SinglePoint) #OLD
    p1 = models.ForeignKey(SinglePoint, related_name='p1_set') #NEW
    p2 = models.ForeignKey(SinglePoint, related_name='p2_set') #NEW
    obs = models.ManyToManyField(Observation, blank=True)
    conds = models.ManyToManyField(Condition, blank=True)
    objects = models.GeoManager()

class Meta:
    order_with_respect_to = 'p1'

在我的view.py中：

...
p1_points = SinglePoint.objects.filter(p1_set__vektordata__order__project__slug=slug)
p2_points = SinglePoint.objects.filter(p2_set__vektordata__order__project__slug=slug)
...

在我切换到ForeignKey之前，它适用于：

points = SinglePoint.objects.filter(connection__vektordata__order__project__slug=slug)

如何将这两个QuerySet连接到一个QuerySet并创建一个distinct（）？

谢谢！

Answer 1

我花了一段时间才找到这个

all_points = p1_points | p2_points

Answer 2

我不熟悉geodjango，但可以通过Q-Object和Boolean Operators将QuerySets组合成一个QuerySet。见http://docs.djangoproject.com/en/dev/topics/db/queries/#complex-lookups-with-q-objects

示例：

Q(p1_points) | Q(p2_points)

我无法帮助你，因为我不确定你想要完成什么。

Answer 3

我认为Q queries可以实现您的需求：

points = SinglePoint.objects.filter(
    Q(p1_set__vektordata__order__project__slug=slug) |
    Q(p2_set__vektordata__order__project__slug=slug)
).distinct()

Answer 4

p1_points.union(p2_points)

请参见Docs

如何将2个Django QuerySets合并为一个并生成SELECT DISTINCT

4 个答案: