Way to sort via related objects?

[rlafuente]

So far I couldn't find a way to sort through a related object's field.
Quick and dirty example:

class Blog(models.Model):
    name = models.CharField()
    type = models.CharField()

class Entry(models.Model):
    name = models.CharField()
    blog = models.ForeignKey(Blog)

And i have a table for Entries with three headers: Entry name, Blog name and Blog type.
I can sort the table by Entry name and Blog name, but not by Blog type. If i try

{% anchor 'blog.type' %}

It comes up with a TemplateSyntaxError:
Caught an exception while rendering: missing FROM-clause entry for table "blog"
LINE 1: ...ND NOT ("testapp_entry"."id" IN (110))) ORDER BY "blog...

I'm wondering if there's a bug in here or if it's simply not implemented. A
pointer of what code to check would be great, i could try and fix/add it
myself. I'm betting that this can be accomplished by tweaking
templatetags/sorting_tags.py, but i can't discern how it could be done.

By the way, awesome extension! It was such a pleasure doing away with my hardcoded sorting code :-)

[copiesofcopies]

I ran into this myself, and found that you can do this by using django's double-underscore syntax, so above you would want to use "blog__type".

Hope this helps, 8 months later ;)

[rlafuente]

It definitely helps -- many thanks! Weirdly enough, i've been working on another part of my app and was now about to rewrite the sorting code because of this apparent shortcoming.

So thanks a ton for the solution -- it's never late! :)

[copiesofcopies]

Excellent! Glad you were tracking the bug and able to use this! Totally makes my day.

[copiesofcopies]

Added a foreign key to the example in the wiki so that others can find this as well.