本文介绍了如何将2个Django QuerySets合并在一起,并进行SELECT DISTINCT的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!
问题描述
model.py class SinglePoint(models.Model):
attributes = models.TextField(blank = True)
name = models.CharField(max_length = 100)
geom = models.PointField()#Kartenposition
objects = models.GeoManager()
类连接(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:
...
p1_points =单点.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,使用:
points = SinglePoint.objects.filter(connection__vektordata__order__project__slug = slug)
如何将这两个QuerySets加入到一个QuerySet中并创建一个distinct()?
解决方案
花了我一段时间找到这个
all_points = p1_points | p2_points
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'
In my view.py:
...
p1_points = SinglePoint.objects.filter(p1_set__vektordata__order__project__slug=slug)
p2_points = SinglePoint.objects.filter(p2_set__vektordata__order__project__slug=slug)
...
Before I switched to ForeignKey, it worked with:
points = SinglePoint.objects.filter(connection__vektordata__order__project__slug=slug)
How to 'join' these two QuerySets to one QuerySet and make a distinct()?
Thanks!
解决方案
It took me a while to find this
all_points = p1_points | p2_points
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