add new tables and models for join through association

spec/schema.rb

@@ -44,4 +44,19 @@ ActiveRecord::Schema.define do
     t.string :name
     t.timestamps null: false
   end
+
+  create_table :players, force: true do |t|
+    t.string :name
+    t.string :value
+    t.timestamps null: false
+  end
+
+  create_table :ptags, force: true do |t|
+    t.string :value
+  end
+
+  create_table :taggings, force: true do |t|
+    t.belongs_to :player
+    t.belongs_to :ptag
+  end
 end