Opened 14 years ago

Closed 14 years ago

#1245 closed defect (fixed)

[patch] Admin interface broken for OneToOne relations

Reported by: gattomatto Owned by: Adrian Holovaty
Component: contrib.admin Version: 0.91
Severity: major Keywords:
Cc: Triage Stage: Unreviewed
Has patch: yes Needs documentation: no
Needs tests: no Patch needs improvement: no
Easy pickings: UI/UX:


We inserted the Places and Restaurantes code verbatim as in example

We addes META classes with an admin attribute (only), to activate the Admin interface.

If we try to administer the Restaurants objects, we got this error on Postgresql:

ProgrammingError at /admin/exemplemodel/restaurants/
ERROR: missing FROM-clause entry for table "exemplemodel_places" 
SELECT "exemplemodel_restaurants"."place_id","exemplemodel_restaurants"."serves_hot_dogs","exemplemodel_restaurants"."serves_pizza" 
FROM "exemplemodel_restaurants" ORDER BY "exemplemodel_places"."id" DESC )

If the Postgres database is configured with "add_missing_from = true", which is the default, you don't get any error but Restaurants lines get listed twice, because of a cartesian product between the two tables.

We think that the ORDER BY clause is generated incorrectly, citing the wrong table/object.
We're using Django 0.91.

Attachments (1)

admin_views_main.diff (936 bytes) - added by Jorge Gajon <gajon@…> 14 years ago.
Fix lookup_order_field for OneToOne fields

Download all attachments as: .zip

Change History (7)

comment:1 Changed 14 years ago by berto

I am getting a similar error where I get duplicate entries in the admin interface. I have the following:

class Blurb(meta.Model):

class Photo(meta.Model):
    blurb = meta.OneToOneField(Blurb)

class Journal(meta.Model):
    blurb = meta.OneToOneField(blurb)

The more Blurbs that get added, the crazier the duplicates that occur in the Photo and Journal interfaces. This behavior seems to indicate it's a matter of adding a where clause in the query that joins the Journal's id with the blurb's id.

comment:2 Changed 14 years ago by bruno@…

Version: 0.91

Same problem here. Two hints, FWIW:

  • the get_list() method works fine (no duplicate),
  • adding an 'ordering' in the class declaring the OneToOneField solves the problem in the admin ChangeList.

comment:3 Changed 14 years ago by bruno@…

After a bit more search here, it seems to be the same problem as #930.

comment:4 Changed 14 years ago by Jorge Gajon <gajon@…>

Summary: Admin interface broken for OneToOne relations[patch] Admin interface broken for OneToOne relations

Hi, I recently found this problem too.

I found that when the view is constructing the lookup_order_field, it tests if the ordering field is a foreign key like this:

if isinstance(lookup_opts.get_field(order_field).rel, meta.ManyToOneRel):
    f = lookup_opts.get_field(order_field)
    rel_ordering = and[0] or
    lookup_order_field = '%s.%s' % (, rel_ordering)

But since a OneToOneRel is also an istance of a ManyToOneRel, that isinstance() evaluates to true, thus constructing this incorrect lookup_order_field (as shown in the problem description above):


What I did was to first test if the field is a OneToOne field and construct the lookup_order_field correctly:

f = lookup_opts.get_field(order_field)
if isinstance(f.rel, meta.OneToOneRel):
    lookup_order_field = '%s' % (f.column,)
elif isinstance(f.rel, meta.ManyToOneRel):
    rel_ordering = and[0] or
    lookup_order_field = '%s.%s' % (, rel_ordering)

I'm attaching a patch.

I'm not really familiar with all the rest of the code, so it may be possible that I'm not considering other circumstances but I have had no problems so far.


Changed 14 years ago by Jorge Gajon <gajon@…>

Attachment: admin_views_main.diff added

Fix lookup_order_field for OneToOne fields

comment:5 Changed 14 years ago by Jorge Gajon <gajon@…>

priority: normalhigh
Severity: normalmajor

Upping the priority since the admin interface is unusable when this problem appears.

Tickets #877 and #930 describe the same problem, they could be marked as duplicates.

comment:6 Changed 14 years ago by jkocherhans

Resolution: fixed
Status: newclosed

(In [2720]) magic-removal: fixed #1245. For models with a OneToOneField and no ordering specified, the admin change_list now orders by the OneToOneField rather than trying to order by the related object's ordering. Use the ordering and list_select_related options to do otherwise.

Note: See TracTickets for help on using tickets.
Back to Top