| 1 | from django.db import models
|
|---|
| 2 |
|
|---|
| 3 | class ModelA(models.Model):
|
|---|
| 4 | name = models.CharField(max_length=100)
|
|---|
| 5 |
|
|---|
| 6 | def __unicode__(self):
|
|---|
| 7 | return self.name
|
|---|
| 8 |
|
|---|
| 9 | class ModelB(models.Model):
|
|---|
| 10 | name = models.CharField(max_length=100)
|
|---|
| 11 | somebool = models.BooleanField(default=True)
|
|---|
| 12 | a = models.ForeignKey(ModelA)
|
|---|
| 13 |
|
|---|
| 14 | def __unicode__(self):
|
|---|
| 15 | return self.name
|
|---|
| 16 |
|
|---|
| 17 | from django.db.models.aggregates import Count
|
|---|
| 18 | __test__ = {"doctest": """
|
|---|
| 19 | >>> a = ModelA.objects.create(name="testA")
|
|---|
| 20 | >>> b1 = ModelB.objects.create(name="B1", a=a, somebool=True)
|
|---|
| 21 | >>> b2 = ModelB.objects.create(name="B2", a=a, somebool=True)
|
|---|
| 22 | >>> ModelA.objects.all().annotate(num_b=Count('modelb')).filter(modelb__somebool=True)[0].num_b
|
|---|
| 23 | 2
|
|---|
| 24 | """}
|
|---|