> I'm pretty confident that David would ensure ActiveRecord works just
> fine with the above scenario.  What you have to type in, I'm not sure.
> But something like this should do.
>
>   class Project < ActiveRecord::Base
>     has_one :manager
>   end
>
>   class Manager < ActiveRecord::Base
>     has_many :project
>   end

Actually, that's the primary difference between belongs_to and has_one. 
With belongs_to, you accept responsibility for the foreign key. With 
has_one, you expect the other side to hold it. So in your example, it 
would be:

   class Project < ActiveRecord::Base
     belongs_to :manager
   end

   class Manager < ActiveRecord::Base
     has_many :projects
   end

P.S.: Note that "has_many" expects the symbol as a plural if it is to 
do automated mapping.
--
David Heinemeier Hansson,
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