I have a rails 3 project where the index.html.erb currently includes <td><%= chapter.university_id %></td>
whereas what I want it to show should be <开发者_StackOverflow;td><%= chapter.university.name %></td>
however, this is currently throwing the exception undefined method `name' for nil:NilClass Interestingly, chapter.foo.name is working to access information from another model to which "chapter" belongs. Can anyone help standardize this?
EDIT:
In an attempt to replicate this error in another way, I changed <td><%= chapter.university.name %></td>
to <td><%= chapter.university.id %></td>
, hoping that I could convince rails to give me university_id from the universities table, rather than the chapters table. Still no luck, but gave the error Called id for nil, which would mistakenly be 4 -- if you really wanted the id of nil, use object_id rather than undefined method `name' for nil:NilClass which I had previously been receiving.
I have also checked and re-checked the 'has_many'/'belongs_to' relationships between chapter
and university
as well as chapter
and foo
and found the working and non-working relationships to be identical. I have even gone so far as to switch the order in which those relationships are declared within the models, to no effect.
This turns out to have been a problem with the way fixtures were loading into the database. Dependencies were not being observed, and so random data was being placed into the university_id column on the universities table. Cleaning out the bad data and replacing it with manually entered data solved the problem.
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