[soc2009/model-validation] Merget to trunk at r12009

git-svn-id: http://code.djangoproject.com/svn/django/branches/soc2009/model-validation@12014 bcc190cf-cafb-0310-a4f2-bffc1f526a37

docs/ref/models/fields.txt

@@ -299,6 +299,18 @@ according to available IDs. You usually won't need to use this directly; a
 primary key field will automatically be added to your model if you don't specify
 otherwise. See :ref:`automatic-primary-key-fields`.
 
+``BigIntegerField``
+-------------------
+
+.. versionadded:: 1.2
+
+.. class:: BigIntegerField([**options])
+
+A 64 bit integer, much like an :class:`IntegerField` except that it is
+guaranteed to fit numbers from -9223372036854775808 to 9223372036854775807. The
+admin represents this as an ``<input type="text">`` (a single-line input).
+ 
+
 ``BooleanField``
 ----------------
 
@@ -543,7 +555,7 @@ By default, :class:`FileField` instances are
 created as ``varchar(100)`` columns in your database. As with other fields, you
 can change the maximum length using the :attr:`~CharField.max_length` argument.
 
-.. _`strftime formatting`: http://docs.python.org/lib/module-time.html#l2h-1941
+.. _`strftime formatting`: http://docs.python.org/library/time.html#time.strftime
 
 ``FilePathField``
 -----------------

docs/ref/models/index.txt

@@ -1,5 +1,6 @@
 .. _ref-models-index:
 
+======
 Models
 ======
 

docs/ref/models/options.txt

@@ -4,8 +4,9 @@
 Model ``Meta`` options
 ======================
 
-This document explains all the possible :ref:`metadata options <meta-options>`  that you can give your model in its internal
-``class Meta``.
+This document explains all the possible :ref:`metadata options
+<meta-options>` that you can give your model in its internal ``class
+Meta``.
 
 Available ``Meta`` options
 ==========================
@@ -242,4 +243,3 @@ The plural name for the object::
     verbose_name_plural = "stories"
 
 If this isn't given, Django will use :attr:`~Options.verbose_name` + ``"s"``.
-

docs/ref/models/querysets.txt

@@ -94,7 +94,7 @@ the query construction and is not part of the public API. However, it is safe
 (and fully supported) to pickle and unpickle the attribute's contents as
 described here.
 
-.. _pickle: http://docs.python.org/lib/module-pickle.html
+.. _pickle: http://docs.python.org/library/pickle.html
 
 .. _queryset-api:
 
@@ -874,6 +874,24 @@ logically::
     # existing set of fields).
     Entry.objects.defer("body").only("headline", "body")
 
+``using(alias)``
+~~~~~~~~~~~~~~~~~~
+
+.. versionadded:: 1.2
+
+This method is for controlling which database the ``QuerySet`` will be
+evaluated against if you are using more than one database.  The only argument
+this method takes is the alias of a database, as defined in
+:setting:`DATABASES`.
+
+For example::
+
+    # queries the database with the 'default' alias.
+    >>> Entry.objects.all()
+
+    # queries the database with the 'backup' alias
+    >>> Entry.objects.using('backup')
+
 
 QuerySet methods that do not return QuerySets
 ---------------------------------------------
@@ -1019,7 +1037,8 @@ Example::
 
 ``count()`` performs a ``SELECT COUNT(*)`` behind the scenes, so you should
 always use ``count()`` rather than loading all of the record into Python
-objects and calling ``len()`` on the result.
+objects and calling ``len()`` on the result (unless you need to load the
+objects into memory anyway, in which case ``len()`` will be faster).
 
 Depending on which database you're using (e.g. PostgreSQL vs. MySQL),
 ``count()`` may return a long integer instead of a normal Python integer. This
@@ -1112,6 +1131,20 @@ control the name of the aggregation value that is returned::
 For an in-depth discussion of aggregation, see :ref:`the topic guide on
 Aggregation <topics-db-aggregation>`.
 
+``exists()``
+~~~~~~~~~~~~
+
+.. versionadded:: 1.2
+
+Returns ``True`` if the :class:`QuerySet` contains any results, and ``False``
+if not. This tries to perform the query in the simplest and fastest way
+possible, but it *does* execute nearly the same query. This means that calling
+:meth:`QuerySet.exists()` is faster than ``bool(some_query_set)``, but not by
+a large degree.  If ``some_query_set`` has not yet been evaluated, but you know
+that it will be at some point, then using ``some_query_set.exists()`` will do
+more overall work (an additional query) than simply using
+``bool(some_query_set)``.
+
 .. _field-lookups:
 
 ``exists()``