In the following models TexasCity inherits from City:
from django.contrib.gis.db import models
class City(models.Model):
name = models.CharField(max_length=30)
point = models.PointField()
objects = models.GeoManager()
def __unicode__(self): return self.name
class TexasCity(City):
tx_county = models.CharField(max_length=30)
objects = models.GeoManager() # Why does this need to be explicit?
def __unicode__(self):
return '%s (%s County)' % (self.name, self.tx_county)
When performing the following query:
In [4]: qs = TexasCity.objects.distance(pnt)
This SQL is generated, which is incorrect (there is no "point" column on the TexasCity model):
In [23]: qs.query.as_sql()
Out[23]:
(u'SELECT (ST_distance_sphere("tz_texascity"."point",%s)) AS "distance", "tz_city"."id", "tz_city"."name", "tz_city"."point", "tz_texascity"."city_ptr_id", "tz_texascity"."tx_county" FROM "tz_texascity" INNER JOIN "tz_city" ON ("tz_texascity"."city_ptr_id" = "tz_city"."id")',
(<django.contrib.gis.db.backend.postgis.adaptor.PostGISAdaptor object at 0x319b610>,))
