Forward references in models

[Jeremy Dunck]

How do others deal with circular refences in their models?

I am building an app with models based on the existing mediawiki schema.

In that schema, for the purpose of this question, there are 3 tables:
page, revision, and text.

page is the whole page represented over time.
revision is a single revision of the page.
text is the content of 1 or more revisions (possibly more due to reverts).

page 1->M revision M->1 text (so far)

however, for performance reasons, page also has a reference to the
latest text record.


page 1->M revision M->1 text
\======1-1=======/^

So, when declaring the model, I had

class MwPage(meta.Model):
..
page_latest = meta.ForeignKey(MwText)


class MwText(meta.Model):
...

class MwRevision(meta.Model):
...
page = meta.ForeignKey(MwPage, verbose_name="page of revision")
text = meta.ForeignKey(MwText, verbose_name="FK to mw_text.old_id")

Except that page_latest complained that MwText didn't exist yet.

So I did a lame stub:

class MwText:
pass

before MwPage.

This seems to mostly work, but (for example) django-admin.py sql emits
two create statements for MwText.

Has anyone else had this problem, and if so, what was your approach?