Fixed -- Doc'd django.contrib.postgres.fields.hstore.KeyTransform().
@@ -319,6 +319,22 @@ transform do not change. For example::
valid for a given field. This can be done using the
:class:`~django.contrib.postgres.validators.KeysValidator`.
+KeyTransform() expression
+-------------------------
+
+.. class:: hstore.KeyTransform(key_name, *args, **kwargs)
+
+Returns the value of the given ``key_name``. This allows you to annotate a key
+value. For example::
+
+ >>> from django.contrib.postgres.fields.hstore import KeyTransform
+ >>> Dog.objects.create(name="Rufus", data={"breed": "labrador"})
+ >>> Dog.objects.create(name="Meg", data={"breed": "collie", "owner": "Bob"})
+
+ >>> rufus = Dog.objects.annotate(breed=KeyTransform("breed", "data"))[0]
+ >>> rufus.breed
+ 'labrador'
+
Querying ``HStoreField``
------------------------
