title: NoMethodError (undefined method `val' for #<Arel::Nodes::BindParam:0x007f4c99d64cb8>):
body: <p>On my local server, I have no issues creating new posts, however, I run into this error when I try to create a new post on my live app hosted on Heroku. </p>
  
  <p>In my research, I found some solutions that haven't worked for me. For example, <a href="https://stackoverflow.com/questions/27671756/rails-arel-unit-test-error">this post</a> mentions updating the schema appropriately-- I would need more help on how the schema should be updated. I also found that <a href="https://stackoverflow.com/questions/27139007/cant-migrate-database-after-scaffold-section-2-2-ruby-on-rails-tutorial-michae">updating the gemfile</a> to include the latest version of the Arel gem worked for some people, but nothing changed for me. My URL is www.humanify.biz/listings and I find the following error in my Heroku logs when I click "New Listing". My git repository is <a href="https://github.com/vsquared10/humanifymvp" rel="nofollow noreferrer">here</a>.</p>
  
  <p>Here's my error:</p>
  
  <pre><code>NoMethodError (undefined method `val' for #&lt;Arel::Nodes::BindParam:0x007f4c99d64cb8&gt;):
  2015-04-10T23:23:56.722453+00:00 app[web.1]:   app/controllers/listings_controller.rb:19:in `new'
  2015-04-10T23:23:56.722454+00:00 app[web.1]: 
  2015-04-10T23:23:56.722456+00:00 app[web.1]: 
  2015-04-10T23:23:56.593393+00:00 app[web.1]: Processing by ListingsController#new as HTML
  2015-04-10T23:23:56.604678+00:00 app[web.1]: Completed 500 Internal Server Error in 11ms
  2015-04-10T23:23:56.716183+00:00 app[web.1]: Processing by ListingsController#new as HTML
  2015-04-10T23:23:56.721356+00:00 app[web.1]: Completed 500 Internal Server Error in 5ms
  </code></pre>
  
  <p>And here is the relevant error line my app/controllers/listings_controller.rb file:</p>
  
  <pre><code># GET /listings/new
    def new
      @listing = current_user.listings.build
    end
  </code></pre>
  
  <p>Here is the models/listings.rb file: </p>
  
  <pre><code>class Listing &lt; ActiveRecord::Base
      belongs_to :user
  
      has_attached_file :image, :styles =&gt; { :medium =&gt; "300x300&gt;", :thumb =&gt; "100x100&gt;" }, :default_url =&gt; "small_Humanify.png"
      # Validate content type
    validates_attachment_content_type :image, :content_type =&gt; /\Aimage/
  end
  </code></pre>
  
  <p>Finally, here is my schema.rb file:</p>
  
  <pre><code>ActiveRecord::Schema.define(version: 20150410191114) do
  
    create_table "listings", force: :cascade do |t|
      t.string   "description"
      t.datetime "created_at",         null: false
      t.datetime "updated_at",         null: false
      t.integer  "user_id"
      t.string   "image_file_name"
      t.string   "image_content_type"
      t.integer  "image_file_size"
      t.datetime "image_updated_at"
    end
  
    add_index "listings", ["user_id"], name: "index_listings_on_user_id"
  
    create_table "users", force: :cascade do |t|
      t.string   "email",                  default: "", null: false
      t.string   "encrypted_password",     default: "", null: false
      t.string   "reset_password_token"
      t.datetime "reset_password_sent_at"
      t.datetime "remember_created_at"
      t.integer  "sign_in_count",          default: 0,  null: false
      t.datetime "current_sign_in_at"
      t.datetime "last_sign_in_at"
      t.string   "current_sign_in_ip"
      t.string   "last_sign_in_ip"
      t.datetime "created_at"
      t.datetime "updated_at"
    end
  
    add_index "users", ["email"], name: "index_users_on_email", unique: true
    add_index "users", ["reset_password_token"], name: "index_users_on_reset_password_token", unique: true
  
  end
  </code></pre>