Edited some docs/db-api.txt changes

parameters.

**New in Django development version:** The syntax for ordering across related

models has changed. See the `Django 0.96 documentation`_ for the old behaviour.

models has changed. See the `Django 0.96 documentation`_ for the old behavior.

.. _Django 0.96 documentation: http://www.djangoproject.com/documentation/0.96/model-api/#floatfield

**New in Django development version**

If you want to reverse the order in which a queryset's elements are returned,

you can use the ``reverse()`` method. Calling ``reverse()`` a second time

restores the ordering back to the normal direction.

Use the ``reverse()`` method to reverse the order in which a queryset's

elements are returned. Calling ``reverse()`` a second time restores the

ordering back to the normal direction.

To retrieve the ''last'' five items in a queryset, you could do this::

Python. The above example will return the last item first, then the

penultimate item and so on. If we had a Python sequence and looked at

``seq[:-5]``, we would see the fifth-last item first. Django doesn't support

that mode of access (slicing from the end), since it is not possible to do it

that mode of access (slicing from the end), because it's not possible to do it

efficiently in SQL.

``distinct()``

the entries in the first filter. We are filtering the ``Blog`` items with each

filter statement, not the ``Entry`` items.

All of this behaviour also applies to ``exclude()``: all the conditions in a

All of this behavior also applies to ``exclude()``: all the conditions in a

single ``exclude()`` statement apply to a single instance (if those conditions

are talking about the same multi-valued relation). Conditions in subsequent

``filter()`` or ``exclude()`` calls that refer to the same relation may end up

**New in Django development version**

Sometimes you want to set a field to a particular value for all the objects in

a queryset. You can do this with the ``update()`` method. For example::

a ``QuerySet``. You can do this with the ``update()`` method. For example::

    # Update all the headlines to the same value.

    Entry.objects.all().update(headline='Everything is the same')

    # Update all the headlines with pub_date in 2007.

    Entry.objects.filter(pub_date__year=2007).update(headline='Everything is the same')

You can only set non-relation fields and ``ForeignKey`` fields using this

method and the value you set the field to must be a normal Python value (you

can't set a field to be equal to some other field at the moment).

method, and the value you set the field to must be a hard-coded Python value

(i.e., you can't set a field to be equal to some other field at the moment).

To update ``ForeignKey`` fields, set the new value to be the new model

instance you want to point to. Example::

    b = Blog.objects.get(pk=1)

    # Make all entries belong to this blog.

    # Change every Entry so that it belongs to this Blog.

    Entry.objects.all().update(blog=b)

The ``update()`` method is applied instantly and doesn't return anything

(similar to ``delete()``). The only restriction on the queryset that is

(similar to ``delete()``). The only restriction on the ``QuerySet`` that is

updated is that it can only access one database table, the model's main

table. So don't try to filter based on related fields or anything like that;

it won't work.