GeoDjango Scale/Layers issue?

Question

I've been having issues visualising data from a shapefile in GeoDjango using OpenStreetMap. I believe it's some sort of a scale issue because of how it appears (as you can see in the screenshot of the admin interface).

I've stored the data in a PostGIS database and set up the model using django as advised in the documentation. Another interesting thing to note is that loading up the data using QGIS works perfectly and looks exactly like the shapefile. Any ideas as to what I should try next?

I'd also be happy to post any code if people need to see it but I am new to GIS stuff and don't quite know what anyone would need to see right away.

Answer 1

So from what you describe I think you might just be interpreting the admin interface in the wrong way. When you set up a model in Django that contains a polygon field, such as

class MyModel(models.Model):
    Mpoly = models.MultiPolygonField()
    objects = models.GeoManager()

Then each model instance represents only one row from your shapefile or your DB table. When loading a shapefile, the parser will create many MyModel instances, one per row of your shapefile.

So my guess is that the admin screenshot you posted is the admin page for one such instance, which will only show one polygon from your table. The GeoDjango admin interface will not show you your entire layer on a map. If you are on the page of one instance, for example /admin/mymodel/23 then the polygon you see is the one corresponding one row in your DB.

In QGis, you access an entire table on a PostGIS database, which shows you all MyModel instances at once on the map. The attributes of each geometry are then the other model fields you might have in your model definition.