I can import a CSV file and create a new object (listing in this case) using the attributes from a single model.
I put this in the Listing model
accepts_nested_attributes_for :address
where address is an associated model (address has many listings, listing belongs to address).
I thought I'd then be able to mass assign attributes from the address model also when importing the CSV file but I get the error:
Can't mass-assign protected attributes: unit_number
where unit_number in one of the attributes in the address model (it's in attr accessible).