app/django/contrib/gis/tests/layermap/models.py
author Sverre Rabbelier <srabbelier@gmail.com>
Wed, 02 Sep 2009 10:24:10 +0200
changeset 2854 003a84e774e2
parent 323 ff1a9aa48cfd
permissions -rw-r--r--
Add support for prefetching fields This makes it possible to specify the fields that should be prefetched as part of a getForFields query. Doing a prefetch on a ReferenceProperty when it is known that the property will be referenced in (almost all) entities is far more efficient than doing the invididual fetches sequentially.

from django.contrib.gis.db import models

class State(models.Model):
    name = models.CharField(max_length=20)
    objects = models.GeoManager()

class County(models.Model):
    name = models.CharField(max_length=25)
    state = models.ForeignKey(State)
    mpoly = models.MultiPolygonField(srid=4269) # Multipolygon in NAD83
    objects = models.GeoManager()

class CountyFeat(models.Model):
    name = models.CharField(max_length=25)
    poly = models.PolygonField(srid=4269)
    objects = models.GeoManager()

class City(models.Model):
    name = models.CharField(max_length=25)
    population = models.IntegerField()
    density = models.DecimalField(max_digits=7, decimal_places=1)
    dt = models.DateField()
    point = models.PointField()
    objects = models.GeoManager()

class Interstate(models.Model):
    name = models.CharField(max_length=20)
    length = models.DecimalField(max_digits=6, decimal_places=2)
    path = models.LineStringField()
    objects = models.GeoManager()

# Mapping dictionaries for the models above.
co_mapping = {'name' : 'Name',
              'state' : {'name' : 'State'}, # ForeignKey's use another mapping dictionary for the _related_ Model (State in this case).
              'mpoly' : 'MULTIPOLYGON', # Will convert POLYGON features into MULTIPOLYGONS.
              }

cofeat_mapping = {'name' : 'Name',
                  'poly' : 'POLYGON',
                  }

city_mapping = {'name' : 'Name',
                'population' : 'Population',
                'density' : 'Density',
                'dt' : 'Created',
                'point' : 'POINT',
                }

inter_mapping = {'name' : 'Name',
                 'length' : 'Length',
                 'path' : 'LINESTRING',
                 }