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Fixed #14758 - Remove entire method signatures from QuerySet headings - thanks adamv for the patch. 

git-svn-id: http://code.djangoproject.com/svn/django/trunk@14737 bcc190cf-cafb-0310-a4f2-bffc1f526a37
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Timo Graham 2010-11-28 18:15:40 +00:00
parent 676c28ce8c
commit b31a956d57
1 changed files with 93 additions and 89 deletions
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182
docs/ref/models/querysets.txt
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@ -119,22 +119,23 @@ described here.
QuerySet API QuerySet API
============ ============
Though you usually won't create one manually -- you'll go through a :class:`Manager` -- here's the formal declaration of a ``QuerySet``: Though you usually won't create one manually -- you'll go through a
:class:`Manager` -- here's the formal declaration of a ``QuerySet``:
.. class:: QuerySet([model=None]) .. class:: QuerySet([model=None])
Usually when you'll interact with a ``QuerySet`` you'll use it by :ref:`chaining Usually when you'll interact with a ``QuerySet`` you'll use it by :ref:`chaining
filters <chaining-filters>`. To make this work, most ``QuerySet`` methods return new querysets. filters <chaining-filters>`. To make this work, most ``QuerySet`` methods return new querysets.
QuerySet methods that return new QuerySets Methods that return new QuerySets
------------------------------------------ ---------------------------------
Django provides a range of ``QuerySet`` refinement methods that modify either Django provides a range of ``QuerySet`` refinement methods that modify either
the types of results returned by the ``QuerySet`` or the way its SQL query is the types of results returned by the ``QuerySet`` or the way its SQL query is
executed. executed.
``filter(**kwargs)`` filter
~~~~~~~~~~~~~~~~~~~~ ~~~~~~
.. method:: filter(**kwargs) .. method:: filter(**kwargs)
@ -145,8 +146,8 @@ The lookup parameters (``**kwargs``) should be in the format described in
`Field lookups`_ below. Multiple parameters are joined via ``AND`` in the `Field lookups`_ below. Multiple parameters are joined via ``AND`` in the
underlying SQL statement. underlying SQL statement.
``exclude(**kwargs)`` exclude
~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~
.. method:: exclude(**kwargs) .. method:: exclude(**kwargs)
@ -180,8 +181,8 @@ In SQL terms, that evaluates to::
Note the second example is more restrictive. Note the second example is more restrictive.
``annotate(*args, **kwargs)`` annotate
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~
.. method:: annotate(*args, **kwargs) .. method:: annotate(*args, **kwargs)
@ -224,8 +225,8 @@ control the name of the annotation::
For an in-depth discussion of aggregation, see :doc:`the topic guide on For an in-depth discussion of aggregation, see :doc:`the topic guide on
Aggregation </topics/db/aggregation>`. Aggregation </topics/db/aggregation>`.
``order_by(*fields)`` order_by
~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~
.. method:: order_by(*fields) .. method:: order_by(*fields)
@ -267,8 +268,8 @@ primary key if there is no ``Meta.ordering`` specified. For example::
...since the ``Blog`` model has no default ordering specified. ...since the ``Blog`` model has no default ordering specified.
Be cautious when ordering by fields in related models if you are also using Be cautious when ordering by fields in related models if you are also using
``distinct()``. See the note in the `distinct()`_ section for an explanation ``distinct()``. See the note in :meth:`distinct` for an explanation of how
of how related model ordering can change the expected results. related model ordering can change the expected results.
It is permissible to specify a multi-valued field to order the results by (for It is permissible to specify a multi-valued field to order the results by (for
example, a ``ManyToMany`` field). Normally this won't be a sensible thing to example, a ``ManyToMany`` field). Normally this won't be a sensible thing to
@ -280,11 +281,6 @@ fields with care and make sure the results are what you expect.
.. versionadded:: 1.0 .. versionadded:: 1.0
If you don't want any ordering to be applied to a query, not even the default
ordering, call ``order_by()`` with no parameters.
.. versionadded:: 1.0
The syntax for ordering across related models has changed. See the `Django 0.96 The syntax for ordering across related models has changed. See the `Django 0.96
documentation`_ for the old behaviour. documentation`_ for the old behaviour.
@ -294,14 +290,17 @@ There's no way to specify whether ordering should be case sensitive. With
respect to case-sensitivity, Django will order results however your database respect to case-sensitivity, Django will order results however your database
backend normally orders them. backend normally orders them.
If you don't want any ordering to be applied to a query, not even the default
ordering, call ``order_by()`` with no parameters.
.. versionadded:: 1.1 .. versionadded:: 1.1
You can tell if a query is ordered or not by checking the You can tell if a query is ordered or not by checking the
:attr:`QuerySet.ordered` attribute, which will be ``True`` if the :attr:`QuerySet.ordered` attribute, which will be ``True`` if the
``QuerySet`` has been ordered in any way. ``QuerySet`` has been ordered in any way.
``reverse()`` reverse
~~~~~~~~~~~~~ ~~~~~~~
.. method:: reverse() .. method:: reverse()
@ -330,8 +329,8 @@ a model which defines a default ordering, or when using
ordering was undefined prior to calling ``reverse()``, and will remain ordering was undefined prior to calling ``reverse()``, and will remain
undefined afterward). undefined afterward).
``distinct()`` distinct
~~~~~~~~~~~~~~ ~~~~~~~~
.. method:: distinct() .. method:: distinct()
@ -345,7 +344,7 @@ query spans multiple tables, it's possible to get duplicate results when a
``QuerySet`` is evaluated. That's when you'd use ``distinct()``. ``QuerySet`` is evaluated. That's when you'd use ``distinct()``.
.. note:: .. note::
Any fields used in an `order_by(*fields)`_ call are included in the SQL Any fields used in an :meth:`order_by` call are included in the SQL
``SELECT`` columns. This can sometimes lead to unexpected results when ``SELECT`` columns. This can sometimes lead to unexpected results when
used in conjunction with ``distinct()``. If you order by fields from a used in conjunction with ``distinct()``. If you order by fields from a
related model, those fields will be added to the selected columns and they related model, those fields will be added to the selected columns and they
@ -363,8 +362,8 @@ query spans multiple tables, it's possible to get duplicate results when a
``values()`` together, be careful when ordering by fields not in the ``values()`` together, be careful when ordering by fields not in the
``values()`` call. ``values()`` call.
``values(*fields)`` values
~~~~~~~~~~~~~~~~~~~ ~~~~~~
.. method:: values(*fields) .. method:: values(*fields)
@ -419,9 +418,11 @@ A few subtleties that are worth mentioning:
>>> Entry.objects.values('blog_id') >>> Entry.objects.values('blog_id')
[{'blog_id': 1}, ...] [{'blog_id': 1}, ...]
* When using ``values()`` together with ``distinct()``, be aware that * When using ``values()`` together with ``distinct()``, be aware that
ordering can affect the results. See the note in the `distinct()`_ ordering can affect the results. See the note in :meth:`distinct` for
section, above, for details. details.
* If you use a ``values()`` clause after an ``extra()`` clause, * If you use a ``values()`` clause after an ``extra()`` clause,
any fields defined by a ``select`` argument in the ``extra()`` any fields defined by a ``select`` argument in the ``extra()``
must be explicitly included in the ``values()`` clause. However, must be explicitly included in the ``values()`` clause. However,
@ -472,8 +473,8 @@ and ``ManyToManyField`` attributes::
pronounced if you include multiple such fields in your ``values()`` query, pronounced if you include multiple such fields in your ``values()`` query,
in which case all possible combinations will be returned. in which case all possible combinations will be returned.
``values_list(*fields)`` values_list
~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~
.. method:: values_list(*fields) .. method:: values_list(*fields)
@ -502,8 +503,8 @@ It is an error to pass in ``flat`` when there is more than one field.
If you don't pass any values to ``values_list()``, it will return all the If you don't pass any values to ``values_list()``, it will return all the
fields in the model, in the order they were declared. fields in the model, in the order they were declared.
``dates(field, kind, order='ASC')`` dates
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~
.. method:: dates(field, kind, order='ASC') .. method:: dates(field, kind, order='ASC')
@ -538,8 +539,8 @@ Examples::
>>> Entry.objects.filter(headline__contains='Lennon').dates('pub_date', 'day') >>> Entry.objects.filter(headline__contains='Lennon').dates('pub_date', 'day')
[datetime.datetime(2005, 3, 20)] [datetime.datetime(2005, 3, 20)]
``none()`` none
~~~~~~~~~~ ~~~~
.. method:: none() .. method:: none()
@ -555,14 +556,14 @@ Examples::
>>> Entry.objects.none() >>> Entry.objects.none()
[] []
``all()`` all
~~~~~~~~~ ~~~
.. method:: all() .. method:: all()
.. versionadded:: 1.0 .. versionadded:: 1.0
Returns a ''copy'' of the current ``QuerySet`` (or ``QuerySet`` subclass you Returns a *copy* of the current ``QuerySet`` (or ``QuerySet`` subclass you
pass in). This can be useful in some situations where you might want to pass pass in). This can be useful in some situations where you might want to pass
in either a model manager or a ``QuerySet`` and do further filtering on the in either a model manager or a ``QuerySet`` and do further filtering on the
result. You can safely call ``all()`` on either object and then you'll result. You can safely call ``all()`` on either object and then you'll
@ -570,8 +571,8 @@ definitely have a ``QuerySet`` to work with.
.. _select-related: .. _select-related:
``select_related()`` select_related
~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~
.. method:: select_related() .. method:: select_related()
@ -691,8 +692,8 @@ related object.
``OneToOneFields`` will not be traversed in the reverse direction if you ``OneToOneFields`` will not be traversed in the reverse direction if you
are performing a depth-based ``select_related``. are performing a depth-based ``select_related``.
``extra(select=None, where=None, params=None, tables=None, order_by=None, select_params=None)`` extra
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~
.. method:: extra(select=None, where=None, params=None, tables=None, order_by=None, select_params=None) .. method:: extra(select=None, where=None, params=None, tables=None, order_by=None, select_params=None)
@ -854,8 +855,8 @@ of the arguments is required, but you should use at least one of them.
Entry.objects.extra(where=['headline=%s'], params=['Lennon']) Entry.objects.extra(where=['headline=%s'], params=['Lennon'])
``defer(*fields)`` defer
~~~~~~~~~~~~~~~~~~ ~~~~~
.. method:: defer(*fields) .. method:: defer(*fields)
@ -882,7 +883,9 @@ deferred set::
# Defers both the body and headline fields. # Defers both the body and headline fields.
Entry.objects.defer("body").filter(rating=5).defer("headline") Entry.objects.defer("body").filter(rating=5).defer("headline")
The order in which fields are added to the deferred set does not matter. Calling ``defer()`` with a field name that has already been deferred is harmless (the field will still be deferred). The order in which fields are added to the deferred set does not matter.
Calling ``defer()`` with a field name that has already been deferred is
harmless (the field will still be deferred).
You can defer loading of fields in related models (if the related models are You can defer loading of fields in related models (if the related models are
loading via ``select_related()``) by using the standard double-underscore loading via ``select_related()``) by using the standard double-underscore
@ -914,8 +917,8 @@ eventually).
bother using ``defer()``; leave it until your query construction has bother using ``defer()``; leave it until your query construction has
settled down and you understand where the hot-points are. settled down and you understand where the hot-points are.
``only(*fields)`` only
~~~~~~~~~~~~~~~~~ ~~~~
.. method:: only(*fields) .. method:: only(*fields)
@ -952,8 +955,8 @@ logically::
# existing set of fields). # existing set of fields).
Entry.objects.defer("body").only("headline", "body") Entry.objects.defer("body").only("headline", "body")
``using(alias)`` using
~~~~~~~~~~~~~~~~ ~~~~~
.. method:: using(alias) .. method:: using(alias)
@ -973,8 +976,8 @@ For example::
>>> Entry.objects.using('backup') >>> Entry.objects.using('backup')
QuerySet methods that do not return QuerySets Methods that do not return QuerySets
--------------------------------------------- ------------------------------------
The following ``QuerySet`` methods evaluate the ``QuerySet`` and return The following ``QuerySet`` methods evaluate the ``QuerySet`` and return
something *other than* a ``QuerySet``. something *other than* a ``QuerySet``.
@ -982,8 +985,8 @@ something *other than* a ``QuerySet``.
These methods do not use a cache (see :ref:`caching-and-querysets`). Rather, These methods do not use a cache (see :ref:`caching-and-querysets`). Rather,
they query the database each time they're called. they query the database each time they're called.
``get(**kwargs)`` get
~~~~~~~~~~~~~~~~~ ~~~
.. method:: get(**kwargs) .. method:: get(**kwargs)
@ -1011,8 +1014,8 @@ The ``DoesNotExist`` exception inherits from
except ObjectDoesNotExist: except ObjectDoesNotExist:
print "Either the entry or blog doesn't exist." print "Either the entry or blog doesn't exist."
``create(**kwargs)`` create
~~~~~~~~~~~~~~~~~~~~ ~~~~~~
.. method:: create(**kwargs) .. method:: create(**kwargs)
@ -1031,12 +1034,12 @@ The :ref:`force_insert <ref-models-force-insert>` parameter is documented
elsewhere, but all it means is that a new object will always be created. elsewhere, but all it means is that a new object will always be created.
Normally you won't need to worry about this. However, if your model contains a Normally you won't need to worry about this. However, if your model contains a
manual primary key value that you set and if that value already exists in the manual primary key value that you set and if that value already exists in the
database, a call to ``create()`` will fail with an ``IntegrityError`` since database, a call to ``create()`` will fail with an :exc:`IntegrityError` since
primary keys must be unique. So remember to be prepared to handle the primary keys must be unique. So remember to be prepared to handle the exception
exception if you are using manual primary keys. if you are using manual primary keys.
``get_or_create(**kwargs)`` get_or_create
~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~
.. method:: get_or_create(**kwargs) .. method:: get_or_create(**kwargs)
@ -1105,8 +1108,8 @@ has a side effect on your data. For more, see `Safe methods`_ in the HTTP spec.
.. _Safe methods: http://www.w3.org/Protocols/rfc2616/rfc2616-sec9.html#sec9.1.1 .. _Safe methods: http://www.w3.org/Protocols/rfc2616/rfc2616-sec9.html#sec9.1.1
``count()`` count
~~~~~~~~~~~ ~~~~~
.. method:: count() .. method:: count()
@ -1131,8 +1134,8 @@ Depending on which database you're using (e.g. PostgreSQL vs. MySQL),
is an underlying implementation quirk that shouldn't pose any real-world is an underlying implementation quirk that shouldn't pose any real-world
problems. problems.
``in_bulk(id_list)`` in_bulk
~~~~~~~~~~~~~~~~~~~~ ~~~~~~~
.. method:: in_bulk(id_list) .. method:: in_bulk(id_list)
@ -1150,8 +1153,8 @@ Example::
If you pass ``in_bulk()`` an empty list, you'll get an empty dictionary. If you pass ``in_bulk()`` an empty list, you'll get an empty dictionary.
``iterator()`` iterator
~~~~~~~~~~~~~~ ~~~~~~~~
.. method:: iterator() .. method:: iterator()
@ -1168,8 +1171,8 @@ been evaluated will force it to evaluate again, repeating the query.
.. _iterator: http://www.python.org/dev/peps/pep-0234/ .. _iterator: http://www.python.org/dev/peps/pep-0234/
``latest(field_name=None)`` latest
~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~
.. method:: latest(field_name=None) .. method:: latest(field_name=None)
@ -1190,8 +1193,8 @@ exist with the given parameters.
Note ``latest()`` exists purely for convenience and readability. Note ``latest()`` exists purely for convenience and readability.
``aggregate(*args, **kwargs)`` aggregate
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~
.. method:: aggregate(*args, **kwargs) .. method:: aggregate(*args, **kwargs)
@ -1224,8 +1227,8 @@ control the name of the aggregation value that is returned::
For an in-depth discussion of aggregation, see :doc:`the topic guide on For an in-depth discussion of aggregation, see :doc:`the topic guide on
Aggregation </topics/db/aggregation>`. Aggregation </topics/db/aggregation>`.
``exists()`` exists
~~~~~~~~~~~~ ~~~~~~
.. method:: exists() .. method:: exists()
@ -1240,8 +1243,8 @@ that it will be at some point, then using ``some_query_set.exists()`` will do
more overall work (an additional query) than simply using more overall work (an additional query) than simply using
``bool(some_query_set)``. ``bool(some_query_set)``.
``update(**kwargs)`` update
~~~~~~~~~~~~~~~~~~~~ ~~~~~~
.. method:: update(**kwargs) .. method:: update(**kwargs)
@ -1265,8 +1268,8 @@ The ``update()`` method does a bulk update and does not call any ``save()``
methods on your models, nor does it emit the ``pre_save`` or ``post_save`` methods on your models, nor does it emit the ``pre_save`` or ``post_save``
signals (which are a consequence of calling ``save()``). signals (which are a consequence of calling ``save()``).
``delete()`` delete
~~~~~~~~~~~~~~~~~~~~ ~~~~~~
.. method:: delete() .. method:: delete()
@ -1736,7 +1739,8 @@ SQL equivalent::
Note this is only available in MySQL and requires direct manipulation of the Note this is only available in MySQL and requires direct manipulation of the
database to add the full-text index. By default Django uses BOOLEAN MODE for database to add the full-text index. By default Django uses BOOLEAN MODE for
full text searches. `Please check MySQL documentation for additional details. <http://dev.mysql.com/doc/refman/5.1/en/fulltext-boolean.html>`_ full text searches. `See the MySQL documentation for additional details.
<http://dev.mysql.com/doc/refman/5.1/en/fulltext-boolean.html>`_
.. fieldlookup:: regex .. fieldlookup:: regex
@ -1805,8 +1809,8 @@ Django provides the following aggregation functions in the
aggregate functions, see aggregate functions, see
:doc:`the topic guide on aggregation </topics/db/aggregation>`. :doc:`the topic guide on aggregation </topics/db/aggregation>`.
``Avg`` Avg
~~~~~~~ ~~~
.. class:: Avg(field) .. class:: Avg(field)
@ -1815,8 +1819,8 @@ Returns the mean value of the given field.
* Default alias: ``<field>__avg`` * Default alias: ``<field>__avg``
* Return type: float * Return type: float
``Count`` Count
~~~~~~~~~ ~~~~~
.. class:: Count(field, distinct=False) .. class:: Count(field, distinct=False)
@ -1832,8 +1836,8 @@ Has one optional argument:
If distinct=True, the count will only include unique instances. This has If distinct=True, the count will only include unique instances. This has
the SQL equivalent of ``COUNT(DISTINCT field)``. Default value is ``False``. the SQL equivalent of ``COUNT(DISTINCT field)``. Default value is ``False``.
``Max`` Max
~~~~~~~ ~~~
.. class:: Max(field) .. class:: Max(field)
@ -1842,8 +1846,8 @@ Returns the maximum value of the given field.
* Default alias: ``<field>__max`` * Default alias: ``<field>__max``
* Return type: same as input field * Return type: same as input field
``Min`` Min
~~~~~~~ ~~~
.. class:: Min(field) .. class:: Min(field)
@ -1852,8 +1856,8 @@ Returns the minimum value of the given field.
* Default alias: ``<field>__min`` * Default alias: ``<field>__min``
* Return type: same as input field * Return type: same as input field
``StdDev`` StdDev
~~~~~~~~~~ ~~~~~~
.. class:: StdDev(field, sample=False) .. class:: StdDev(field, sample=False)
@ -1875,8 +1879,8 @@ Has one optional argument:
available as an extension module for SQLite. Consult the SQlite available as an extension module for SQLite. Consult the SQlite
documentation for instructions on obtaining and installing this extension. documentation for instructions on obtaining and installing this extension.
``Sum`` Sum
~~~~~~~ ~~~
.. class:: Sum(field) .. class:: Sum(field)
@ -1885,8 +1889,8 @@ Computes the sum of all values of the given field.
* Default alias: ``<field>__sum`` * Default alias: ``<field>__sum``
* Return type: same as input field * Return type: same as input field
``Variance`` Variance
~~~~~~~~~~~~ ~~~~~~~~
.. class:: Variance(field, sample=False) .. class:: Variance(field, sample=False)