id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
23589	Django 1.7 filter Q m2m bug	Grafumbly	nobody	"The behavior of Q objects has changed in an undocumented and breaking way for m2m relationships in Django 1.7 from the behavior in 1.6.7, returning different query results depending on the Django version. 

In the case where you want to select a primary object that has related objects of one type, but none of another, you could use a Q like this:
`q = Q(Q(relatedobject__someparam=True), ~Q(relatedobject__someparam=False))`
`results = PrimaryObject.objects.filter(q)`

Using this Q in a filter in 1.6.7 would give you all primary objects that have relatedobjects with someparam=True and omit any primary objects that also had a relatedobject with someparam=False. In 1.7 these objects are returned despite the `~Q(relatedobject__someparam=False)`.

This gist provides a sample to illustrate the problem:
https://gist.github.com/scottsexton/375f7869839a98593695"	Bug	closed	Database layer (models, ORM)	1.7	Normal	invalid			Unreviewed	0	0	0	0	0	0