updated migration code

db/migrate/20170403135934_create_orders.rb

@@ -1,7 +1,7 @@
 class CreateOrders < ActiveRecord::Migration[5.0]
   def change
-    create_table :orders, :id => false, :primary_key => :order_id do |t|
-      t.string :order_id, :limit => 16, :null => false, :index => true, :unique => true #custom foreign_key to prevent conflict during sync
+    create_table :orders, :id => false do |t|
+      t.string :order_id, :limit => 16, :primary_key => true #custom foreign_key to prevent conflict during sync
       t.datetime :date, :null => false
       t.string :source, :null => false, :default => "emenu"
       t.string :order_type, :null => false, :default => "dine-in"