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Fixed #25205 -- Removed doc references to deprecated GeoManager class.

This commit is contained in:
Brendan Hayward 2015-05-08 22:52:15 +05:00 committed by Tim Graham
parent 7fa1dd8a80
commit c9fb4f3c45
8 changed files with 42 additions and 48 deletions

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@ -105,6 +105,7 @@ answer newbie questions, and generally made Django that much better:
Bouke Haarsma <bouke@haarsma.eu>
Božidar Benko <bbenko@gmail.com>
Brant Harris
Brendan Hayward <brendanhayward85@gmail.com>
Brenton Simpson <http://theillustratedlife.com>
Brett Cannon <brett@python.org>
Brett Hoerner <bretthoerner@bretthoerner.com>

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@ -226,18 +226,17 @@ in southern Texas::
# A projected coordinate system (only valid for South Texas!)
# is used, units are in meters.
point = models.PointField(srid=32140)
objects = models.GeoManager()
Then distance queries may be performed as follows::
>>> from django.contrib.gis.geos import *
>>> from django.contrib.gis.geos import fromstr
>>> from django.contrib.gis.measure import D # ``D`` is a shortcut for ``Distance``
>>> from geoapp import SouthTexasCity
>>> from geoapp.models import SouthTexasCity
# Distances will be calculated from this point, which does not have to be projected.
>>> pnt = fromstr('POINT(-96.876369 29.905320)', srid=4326)
# If numeric parameter, units of field (meters in this case) are assumed.
>>> qs = SouthTexasCity.objects.filter(point__distance_lte=(pnt, 7000))
# Find all Cities within 7 km, > 20 miles away, and > 100 chains away (an obscure unit)
# Find all Cities within 7 km, > 20 miles away, and > 100 chains away (an obscure unit)
>>> qs = SouthTexasCity.objects.filter(point__distance_lte=(pnt, D(km=7)))
>>> qs = SouthTexasCity.objects.filter(point__distance_gte=(pnt, D(mi=20)))
>>> qs = SouthTexasCity.objects.filter(point__distance_gte=(pnt, D(chain=100)))

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@ -216,8 +216,9 @@ In the following example, the distance from the city of Hobart to every other
:class:`~django.contrib.gis.db.models.PointField` in the ``AustraliaCity``
queryset is calculated::
>>> from django.contrib.gis.db.models.functions import Distance
>>> pnt = AustraliaCity.objects.get(name='Hobart').point
>>> for city in AustraliaCity.objects.distance('point', pnt):
>>> for city in AustraliaCity.objects.annotate(distance=Distance('point', pnt)):
... print(city.name, city.distance)
Wollongong 990071.220408 m
Shellharbour 972804.613941 m

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@ -629,6 +629,8 @@ Oracle ``SDO_WITHIN_DISTANCE(poly, geom, 5)``
This lookup is not available on SpatiaLite.
.. _geoqueryset-methods:
``GeoQuerySet`` Methods
=======================

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@ -57,7 +57,6 @@ Example
class TestGeo(models.Model):
name = models.CharField(max_length=25) # corresponds to the 'str' field
poly = models.PolygonField(srid=4269) # we want our model in a different SRID
objects = models.GeoManager()
def __str__(self): # __unicode__ on Python 2
return 'Name: %s' % self.name

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@ -14,7 +14,6 @@ of a `Digital Elevation Model`__ as our examples::
class Zipcode(models.Model):
code = models.CharField(max_length=5)
poly = models.PolygonField()
objects = models.GeoManager()
class Elevation(models.Model):
name = models.CharField(max_length=100)
@ -246,36 +245,40 @@ determining `when to use geography data type over geometry data type
.. currentmodule:: django.contrib.gis.db.models
.. class:: GeoManager
In order to conduct geographic queries, each geographic model requires
a ``GeoManager`` model manager. This manager allows for the proper SQL
construction for geographic queries; thus, without it, all geographic filters
will fail.
The ``GeoManager`` is required in order to use the legacy
:ref:`geoqueryset-methods`.
.. note::
.. deprecated:: 1.9
Geographic filtering support is limited to geometry fields. ``RasterField``
does not currently allow spatial querying.
All ``GeoQuerySet`` methods have been deprecated and replaced by
:doc:`equivalent database functions </ref/contrib/gis/functions>`. As soon
as the legacy methods have been replaced in your code, you should be able
to remove the special ``GeoManager`` from your GIS-enabled classes.
It should also be noted that ``GeoManager`` is required even if the
model does not have a geographic field itself, e.g., in the case of a
``ForeignKey`` relation to a model with a geographic field. For example,
if we had an ``Address`` model with a ``ForeignKey`` to our ``Zipcode``
model::
.. versionchanged:: 1.9
from django.contrib.gis.db import models
In older versions, the manager was required to conduct geographic queries.
Without it, all geographic filters failed.
class Address(models.Model):
num = models.IntegerField()
street = models.CharField(max_length=100)
city = models.CharField(max_length=100)
state = models.CharField(max_length=2)
zipcode = models.ForeignKey(Zipcode, on_delete=models.CASCADE)
objects = models.GeoManager()
``GeoManager`` was required even if the model did not have a geographic
field itself, e.g., in the case of a ``ForeignKey`` relation to a model
with a geographic field. For example, if we had an ``Address`` model with
a ``ForeignKey`` to our ``Zipcode`` model::
The geographic manager is needed to do spatial queries on related ``Zipcode`` objects,
for example::
from django.contrib.gis.db import models
qs = Address.objects.filter(zipcode__poly__contains='POINT(-104.590948 38.319914)')
class Address(models.Model):
num = models.IntegerField()
street = models.CharField(max_length=100)
city = models.CharField(max_length=100)
state = models.CharField(max_length=2)
zipcode = models.ForeignKey(Zipcode, on_delete=models.CASCADE)
objects = models.GeoManager()
The geographic manager was needed to do spatial queries on related
``Zipcode`` objects, for example::
qs = Address.objects.filter(zipcode__poly__contains='POINT(-104.590948 38.319914)')
.. rubric:: Footnotes
.. [#fnogc] OpenGIS Consortium, Inc., `Simple Feature Specification For SQL <http://www.opengeospatial.org/standards/sfs>`_.

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@ -238,20 +238,14 @@ model to represent this data::
lon = models.FloatField()
lat = models.FloatField()
# GeoDjango-specific: a geometry field (MultiPolygonField), and
# overriding the default manager with a GeoManager instance.
# GeoDjango-specific: a geometry field (MultiPolygonField)
mpoly = models.MultiPolygonField()
objects = models.GeoManager()
# Returns the string representation of the model.
def __str__(self): # __unicode__ on Python 2
return self.name
Please note two important things:
1. The ``models`` module is imported from ``django.contrib.gis.db``.
2. You must override the model's default manager with
:class:`~django.contrib.gis.db.models.GeoManager` to perform spatial queries.
Note that the ``models`` module is imported from ``django.contrib.gis.db``.
The default spatial reference system for geometry fields is WGS84 (meaning
the `SRID`__ is 4326) -- in other words, the field coordinates are in
@ -579,7 +573,6 @@ directly into the ``models.py`` of a GeoDjango application::
lon = models.FloatField()
lat = models.FloatField()
geom = models.MultiPolygonField(srid=4326)
objects = models.GeoManager()
# Auto-generated `LayerMapping` dictionary for WorldBorder model
worldborders_mapping = {

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@ -455,13 +455,10 @@ Throughout this section, we will use the term "automatic manager" to mean a
manager that Django creates for you -- either as a default manager on a model
with no managers, or to use temporarily when accessing related objects.
Sometimes this default class won't be the right choice. One example is in the
:mod:`django.contrib.gis` application that ships with Django itself. All ``gis``
models must use a special manager class (:class:`~django.contrib.gis.db.models.GeoManager`)
because they need a special queryset (:class:`~django.contrib.gis.db.models.GeoQuerySet`)
to be used for interacting with the database. It turns out that models which require
a special manager like this need to use the same manager class wherever an automatic
manager is created.
Sometimes this default class won't be the right choice. The default manager
may not have all the methods you need to work with your data. A custom manager
class of your own will allow you to create custom ``QuerySet`` objects to give
you the information you need.
Django provides a way for custom manager developers to say that their manager
class should be used for automatic managers whenever it is the default manager
@ -490,8 +487,7 @@ it will use :class:`django.db.models.Manager`.
Writing correct Managers for use in automatic Manager instances
---------------------------------------------------------------
As already suggested by the :mod:`django.contrib.gis` example, above, the
``use_for_related_fields`` feature is primarily for managers that need to
The ``use_for_related_fields`` feature is primarily for managers that need to
return a custom ``QuerySet`` subclass. In providing this functionality in your
manager, there are a couple of things to remember.