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
13073	Duplicate rows when checking ID	jnadro52	nobody	"Hello:

I hope that this is a legitimate bug and I'm not wasting your time with something that is a slight misunderstanding of how the Django database layer works.  Here we go...

I have two tables... a table that holds football matchups (texans vs. giants, for example) and a table that caches the statistics for the game.  The table that caches the statistics would have a row per team, so this is what the data would look like:


{{{
ID       team               opponent              matchup_id
1        texans             giants                1
2        giants             texans                1
}}}


So now I want to retrieve these two rows by matchup ID.  Lets say the model names are ""matchup"" and ""cache"".  So, I attempted to go retrieve them like so:


{{{
caches = cache.objects.filter(matchup=1)
}}}


When I do so, I do get two objects returned, but they are both the same cache row that is returned.  So I would get a QuerySet containing two objects, both of which would have the same primary key.

What really confused me is that if I added a .distinct() method call to the end of that call, I would get the expected results.  If it is the case where there is a join occurring I would understand getting duplicates, even though I would think there should be no join in this call, since i am just checking a foreign key.  The kicker is that I always get row id 2 and never row id 1 when I make this call without the distinct call as well.  If this were a cross-join, I should get multiple duplicates of all rows that meet the criteria, but I do not.

I hope I explained this well enough, please feel free to contact me at my given email if you have any questions."		closed	Database layer (models, ORM)	1.1		invalid			Unreviewed	0	0	0	0	0	0