PointField can't be used in get_or_create

[kemar]

• Django 1.10.2
• PostgreSQL 9.4.9
• PostGIS 2.2.2

With this model:

from django.contrib.gis.db import models as gis_models
from django.db import models as django_models

class MyModel(django_models.Model):
    coords = gis_models.PointField(geography=True)

Try this:

>>> i = MyModel.objects.all()[0]
>>> type(i.coords)
>>> django.contrib.gis.geos.point.Point
>>> MyModel.objects.get_or_create(coords=i.coords)

ValueError: PostGIS geography does not support the "~=" function/operator.

But ​`~=` is a valid operator.

Looks like a bug to me.

[kemar]

Traceback

[Tim Graham]

This is the same error as if you did MyModel.objects.get(coords=i.coords). I'm not a GeoDjango expert but perhaps the issue is that ​a subset of PostGIS spatial lookups are available for geography fields.

[Claude Paroz]

Like Tim said, when using the geography flag, only a subset of methods are available.
See also ​http://postgis.net/docs/PostGIS_Special_Functions_Index.html#PostGIS_TypeFunctionMatrix (the geog column).

[kemar]

Ok, understood. Thanx for the feedback.