Fixtures load inconsistently

Hi all,

I've got a weird problem with loading fixtures, and I'm hoping someone out there can help. I'm having problems running my tests, because for one of my models the fixtures are loading strangely. Here's an example fixture:

john_doe:   status: student   department:   alumni:   title:   applicant:   student_status:   staff:   pref_first_name:   faculty:   applicant_status:   year_in_school: freshman   chair:   pidm: 12345678   reed_id: L12345   program:   middle_initial:   first_name: John   student: Y   login: doej   last_name: Doe   email: doej@reed.edu

This is a model that's wrapping a legacy table. It has no id column. However, its pidm column is the primary key, so in my model I've got:

  set_primary_key :pidm   alias_attribute :id, :pidm

If I load up my fixtures using "rake:fixtures:load RAILS_ENV=test" then everything works just fine. My 5 fixtures for this model go in to the test db exactly as written. However, when I run my test suite, and rails loads the fixtures, 3 of the 5 fixtures load up with their pidm field set to 91.

It's surprising because it's only 3 of the 5. I've been poking at it all morning, with no luck. I've changed data values, etc., and it's always the same 3 that come out with 91. The other 2 fixtures have the pidm that's set in the fixture's yaml file.

Has anybody encountered this? Or does anybody have suggestions?

Thanks!