mirrors/django
1
0
Fork 0
mirror of https://github.com/django/django.git synced 2025-04-07 06:56:40 +00:00
Code Issues 32 Releases Wiki Activity

[1.10.x] Doc'd that model instances with pk=None don't compare equal.

Browse Source 
Backport of 224fe22bf1628c1feff110ce993dcb33880bf3a3 from master
This commit is contained in:
Adam Chainz 2016-10-07 10:40:16 +01:00 committed by Tim Graham
parent c2853807bc
commit 27d352800c
1 changed files with 14 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

19
docs/ref/models/instances.txt
View File

@ -646,9 +646,10 @@ with :func:`~django.utils.encoding.python_2_unicode_compatible` as shown above.
.. method:: Model.__eq__()
The equality method is defined such that instances with the same primary
key value and the same concrete class are considered equal. For proxy
models, concrete class is defined as the model's first non-proxy parent;
for all other models it is simply the model's class.
key value and the same concrete class are considered equal, except that
instances with a primary key value of ``None`` aren't equal to anything except
themselves. For proxy models, concrete class is defined as the model's first
non-proxy parent; for all other models it's simply the model's class.
For example::
@ -664,10 +665,18 @@ For example::
class MultitableInherited(MyModel):
pass
# Primary keys compared
MyModel(id=1) == MyModel(id=1)
MyModel(id=1) == MyProxyModel(id=1)
MyModel(id=1) != MultitableInherited(id=1)
MyModel(id=1) != MyModel(id=2)
# Primay keys are None
MyModel(id=None) != MyModel(id=None)
# Same instance
instance = MyModel(id=None)
instance == instance
# Proxy model
MyModel(id=1) == MyProxyModel(id=1)
# Multi-table inheritance
MyModel(id=1) != MultitableInherited(id=1)
``__hash__()``
--------------