After upgrading to Rails 1.1, a lot of my unit tests broke. Turns out
when I run rake test_units and it migrates the test database, it adds
a not null constraint to every column. I don’t have this specified in
my migration, and apparently it works fine with rake migrate if I do
‘rake migrate RAILS_ENV=test’, the not null constraints aren’t set.
So why when I run tests is it adding the not null constraints? I’m
using PostgreSQL 8.1.0, fwiw.