summaryrefslogtreecommitdiffstats
path: root/bitbake/lib/toaster/contrib/django-aggregate-if-master/README.rst
diff options
context:
space:
mode:
Diffstat (limited to 'bitbake/lib/toaster/contrib/django-aggregate-if-master/README.rst')
-rw-r--r--bitbake/lib/toaster/contrib/django-aggregate-if-master/README.rst156
1 files changed, 0 insertions, 156 deletions
diff --git a/bitbake/lib/toaster/contrib/django-aggregate-if-master/README.rst b/bitbake/lib/toaster/contrib/django-aggregate-if-master/README.rst
deleted file mode 100644
index 739d4daccf..0000000000
--- a/bitbake/lib/toaster/contrib/django-aggregate-if-master/README.rst
+++ /dev/null
@@ -1,156 +0,0 @@
1Django Aggregate If: Condition aggregates for Django
2====================================================
3
4.. image:: https://travis-ci.org/henriquebastos/django-aggregate-if.png?branch=master
5 :target: https://travis-ci.org/henriquebastos/django-aggregate-if
6 :alt: Test Status
7
8.. image:: https://landscape.io/github/henriquebastos/django-aggregate-if/master/landscape.png
9 :target: https://landscape.io/github/henriquebastos/django-aggregate-if/master
10 :alt: Code Helth
11
12.. image:: https://pypip.in/v/django-aggregate-if/badge.png
13 :target: https://crate.io/packages/django-aggregate-if/
14 :alt: Latest PyPI version
15
16.. image:: https://pypip.in/d/django-aggregate-if/badge.png
17 :target: https://crate.io/packages/django-aggregate-if/
18 :alt: Number of PyPI downloads
19
20*Aggregate-if* adds conditional aggregates to Django.
21
22Conditional aggregates can help you reduce the ammount of queries to obtain
23aggregated information, like statistics for example.
24
25Imagine you have a model ``Offer`` like this one:
26
27.. code-block:: python
28
29 class Offer(models.Model):
30 sponsor = models.ForeignKey(User)
31 price = models.DecimalField(max_digits=9, decimal_places=2)
32 status = models.CharField(max_length=30)
33 expire_at = models.DateField(null=True, blank=True)
34 created_at = models.DateTimeField(auto_now_add=True)
35 updated_at = models.DateTimeField(auto_now=True)
36
37 OPEN = "OPEN"
38 REVOKED = "REVOKED"
39 PAID = "PAID"
40
41Let's say you want to know:
42
43#. How many offers exists in total;
44#. How many of them are OPEN, REVOKED or PAID;
45#. How much money was offered in total;
46#. How much money is in OPEN, REVOKED and PAID offers;
47
48To get these informations, you could query:
49
50.. code-block:: python
51
52 from django.db.models import Count, Sum
53
54 Offer.objects.count()
55 Offer.objects.filter(status=Offer.OPEN).aggregate(Count('pk'))
56 Offer.objects.filter(status=Offer.REVOKED).aggregate(Count('pk'))
57 Offer.objects.filter(status=Offer.PAID).aggregate(Count('pk'))
58 Offer.objects.aggregate(Sum('price'))
59 Offer.objects.filter(status=Offer.OPEN).aggregate(Sum('price'))
60 Offer.objects.filter(status=Offer.REVOKED).aggregate(Sum('price'))
61 Offer.objects.filter(status=Offer.PAID).aggregate(Sum('price'))
62
63In this case, **8 queries** were needed to retrieve the desired information.
64
65With conditional aggregates you can get it all with only **1 query**:
66
67.. code-block:: python
68
69 from django.db.models import Q
70 from aggregate_if import Count, Sum
71
72 Offer.objects.aggregate(
73 pk__count=Count('pk'),
74 pk__open__count=Count('pk', only=Q(status=Offer.OPEN)),
75 pk__revoked__count=Count('pk', only=Q(status=Offer.REVOKED)),
76 pk__paid__count=Count('pk', only=Q(status=Offer.PAID)),
77 pk__sum=Sum('price'),
78 pk__open__sum=Sum('price', only=Q(status=Offer.OPEN)),
79 pk__revoked__sum=Sum('price'), only=Q(status=Offer.REVOKED)),
80 pk__paid__sum=Sum('price'), only=Q(status=Offer.PAID))
81 )
82
83Installation
84------------
85
86*Aggregate-if* works with Django 1.4, 1.5, 1.6 and 1.7.
87
88To install it, simply:
89
90.. code-block:: bash
91
92 $ pip install django-aggregate-if
93
94Inspiration
95-----------
96
97There is a 5 years old `ticket 11305`_ that will (*hopefully*) implement this feature into
98Django 1.8.
99
100Using Django 1.6, I still wanted to avoid creating custom queries for very simple
101conditional aggregations. So I've cherry picked those ideas and others from the
102internet and built this library.
103
104This library uses the same API and tests proposed on `ticket 11305`_, so when the
105new feature is available you can easily replace ``django-aggregate-if``.
106
107Limitations
108-----------
109
110Conditions involving joins with aliases are not supported yet. If you want to
111help adding this feature, you're welcome to check the `first issue`_.
112
113Contributors
114------------
115
116* `Henrique Bastos <http://github.com/henriquebastos>`_
117* `Iuri de Silvio <https://github.com/iurisilvio>`_
118* `Hampus Stjernhav <https://github.com/champ>`_
119* `Bradley Martsberger <https://github.com/martsberger>`_
120* `Markus Bertheau <https://github.com/mbertheau>`_
121* `end0 <https://github.com/end0>`_
122* `Scott Sexton <https://github.com/scottsexton>`_
123* `Mauler <https://github.com/mauler>`_
124* `trbs <https://github.com/trbs>`_
125
126Changelog
127---------
128
1290.5
130 - Support for Django 1.7
131
1320.4
133 - Use tox to run tests.
134 - Add support for Django 1.6.
135 - Add support for Python3.
136 - The ``only`` parameter now freely supports joins independent of the main query.
137 - Adds support for alias relabeling permitting excludes and updates with aggregates filtered on remote foreign key relations.
138
1390.3.1
140 - Fix quotation escaping.
141 - Fix boolean casts on Postgres.
142
1430.2
144 - Fix postgres issue with LIKE conditions.
145
1460.1
147 - Initial release.
148
149
150License
151=======
152
153The MIT License.
154
155.. _ticket 11305: https://code.djangoproject.com/ticket/11305
156.. _first issue: https://github.com/henriquebastos/django-aggregate-if/issues/1
generated by cgit v1.2.3-54-g00ecf (git 2.39.0) at 2024-05-27 13:24:39 +0000