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Code Issues 32 Releases Wiki Activity

magic-removal: Fixed section titles in docs/db-api.txt to uncapitalize words, to match our style

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git-svn-id: http://code.djangoproject.com/svn/django/branches/magic-removal@2741 bcc190cf-cafb-0310-a4f2-bffc1f526a37
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Adrian Holovaty 2006-04-23 23:22:42 +00:00
parent 9b8332f7df
commit 24b8ffe10c
1 changed files with 149 additions and 150 deletions
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docs/db-api.txt
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@ -43,7 +43,7 @@ and the following Django sample session::
>>> Poll.objects.all() >>> Poll.objects.all()
[What's up?, What's your name?] [What's up?, What's your name?]
How Queries Work How queries work
================ ================
Querying in Django is based upon the construction and evaluation of Query Querying in Django is based upon the construction and evaluation of Query
@ -62,8 +62,8 @@ you require, it can be evaluated (using iterators, slicing, or one of a range
of other techniques), yielding an object or list of objects that meet the of other techniques), yielding an object or list of objects that meet the
specifications of the Query Set. specifications of the Query Set.
Obtaining an Initial Query Set Obtaining an initial QuerySet
============================== =============================
Every model has at least one Manager; by default, the Manager is called Every model has at least one Manager; by default, the Manager is called
``objects``. One of the most important roles of the Manager is as a source ``objects``. One of the most important roles of the Manager is as a source
@ -84,8 +84,8 @@ and construction of Managers.
.. _Managers: http://www.djangoproject.com/documentation/model_api/#managers .. _Managers: http://www.djangoproject.com/documentation/model_api/#managers
Query Set Refinement QuerySet refinement
==================== ===================
The initial Query Set provided by the Manager describes all objects of a The initial Query Set provided by the Manager describes all objects of a
given type. However, you will usually need to describe a subset of the given type. However, you will usually need to describe a subset of the
@ -304,7 +304,7 @@ See the `OR lookups examples page`_ for more examples.
.. _OR lookups examples page: http://www.djangoproject.com/documentation/models/or_lookups/ .. _OR lookups examples page: http://www.djangoproject.com/documentation/models/or_lookups/
QuerySet evaluation QuerySet evaluation
==================== ===================
A Query Set must be evaluated to return the objects that are contained in the A Query Set must be evaluated to return the objects that are contained in the
set. This can be achieved by iteration, slicing, or by specialist function. set. This can be achieved by iteration, slicing, or by specialist function.
@ -338,7 +338,7 @@ However - be warned; this could have a large memory overhead, as Django will
create an in-memory representation of every element of the list. create an in-memory representation of every element of the list.
Caching and QuerySets Caching and QuerySets
====================== =====================
Each Query Set contains a cache. In a newly created Query Set, this cache Each Query Set contains a cache. In a newly created Query Set, this cache
is unpopulated. When a Query Set is evaluated for the first time, Django is unpopulated. When a Query Set is evaluated for the first time, Django
@ -365,8 +365,8 @@ To avoid this problem, simply save the Query Set and reuse it::
print [p for p in queryset] # Evaluate the query set print [p for p in queryset] # Evaluate the query set
print [p for p in queryset] # Re-use the cache from the evaluation print [p for p in queryset] # Re-use the cache from the evaluation
Specialist Query Set Evaluation Specialist QuerySet evaluation
=============================== ==============================
The following specialist functions can also be used to evaluate a Query Set. The following specialist functions can also be used to evaluate a Query Set.
Unlike iteration or slicing, these methods do not populate the cache; each Unlike iteration or slicing, these methods do not populate the cache; each
@ -450,7 +450,7 @@ to by the relation.
ManyToManyField Object Set Object Set ManyToManyField Object Set Object Set
=============== ============= ============= =============== ============= =============
Single Object Descriptor Single object descriptor
------------------------ ------------------------
If the related object is a single object, the descriptor acts If the related object is a single object, the descriptor acts
@ -490,7 +490,7 @@ a descriptor on an instance is accessed, the database will be
queried, and the result stored. Subsequent attempts to access queried, and the result stored. Subsequent attempts to access
the descriptor on the same instance will use the cached value. the descriptor on the same instance will use the cached value.
Object Set Descriptor Object set descriptor
--------------------- ---------------------
An Object Set Descriptor acts just like the Manager - as an initial Query An Object Set Descriptor acts just like the Manager - as an initial Query
@ -543,7 +543,7 @@ Each of these operations on the Object Set Descriptor has immediate effect
on the database - every add, create and remove is immediately and on the database - every add, create and remove is immediately and
automatically saved to the database. automatically saved to the database.
Relationships and Queries Relationships and queries
========================= =========================
When composing a ``filter`` or ``exclude`` refinement, it may be necessary to When composing a ``filter`` or ``exclude`` refinement, it may be necessary to
@ -563,8 +563,8 @@ example::
attribute that starts with "eggs". Django automatically composes the joins attribute that starts with "eggs". Django automatically composes the joins
and conditions required for the SQL query. and conditions required for the SQL query.
Specialist Query Sets Refinement Specialist QuerySets refinement
================================ ===============================
In addition to ``filter`` and ``exclude()``, Django provides a range of In addition to ``filter`` and ``exclude()``, Django provides a range of
Query Set refinement methods that modify the types of results returned by Query Set refinement methods that modify the types of results returned by
@ -942,4 +942,3 @@ get_FOO_height() and get_FOO_width()
For every ``ImageField``, the object will have ``get_FOO_height()`` and For every ``ImageField``, the object will have ``get_FOO_height()`` and
``get_FOO_width()`` methods, where ``FOO`` is the name of the field. This ``get_FOO_width()`` methods, where ``FOO`` is the name of the field. This
returns the height (or width) of the image, as an integer, in pixels. returns the height (or width) of the image, as an integer, in pixels.