I've got a situation where I'm trying to import a csv and its telling me Unknown Attribute, though I can see the attribute is there and correct.  I had a look with debugger and checked the contents of the customer and customer_hash and everything looks fine to me.  Yet when you try to update, unknown attribute 'account_number'.  Any thoughts?

Error:

unknown attribute 'account_number' for Customer. 

def import
  Customer.import(params[:file])
  redirect_to customers_path, notice: "Customers Imported."
end

  def self.import(file)
    CSV.foreach(file.path, headers: true) do |row|
      customer_hash = row.to_hash
      customer = find_or_create_by!(sla_number: customer_hash['sla_number'])
      customer.update(customer_hash)
    end
  end

 <%= form_tag import_customers_path, multipart: true, class: 'form-inline' do %>
   <%= file_field_tag :file, class: "" %>
   <%= submit_tag "Import CSV", class: "btn btn-info" %>
<% end %>

  create_table "customers", force: :cascade do |t|
    t.string "name"
    t.datetime "created_at", null: false
    t.datetime "updated_at", null: false
    t.string "account_number"
    t.string "sla_number"
    t.string "mobile_phone"
    t.string "work_phone"
    t.string "home_phone"
    t.string "municipality"
    t.string "main_product"
    t.string "contract_name"
    t.date "contract_from"
    t.date "contract_to"
  end

  David Kimura  

I got it working!

  def self.import(file)
    CSV.foreach(file.path, headers: true, header_converters: :symbol) do |row|
      customer_hash = row.to_hash
      customer = find_or_create_by!(sla_number: customer_hash[:sla_number])
      customer.update(customer_hash)
    end
  end