check required for oqs and cashier terminal

app/models/cashier_terminal.rb

@@ -3,4 +3,7 @@ class CashierTerminal < ApplicationRecord
   	has_many :zones, through: :cashier_terminal_by_zones
 
   	scope :available, -> {where(is_currently_login: false)}
+
+  	# validations
+ 	validates_presence_of :name, :printer_name
 end

app/models/order_queue_station.rb

@@ -10,6 +10,9 @@ class OrderQueueStation < ApplicationRecord
 
   scope :active, -> {where(is_active: true)}
 
+  # validations
+  validates_presence_of :station_name, :printer_name
+
   def process_order (order, table_id)    
     oqs_stations = OrderQueueStation.active
     dining=DiningFacility.find(table_id)    

app/models/sale.rb

@@ -858,7 +858,6 @@ end
   def self.hourly_sales(today)
     query= Sale.select("grand_total")
             .where('payment_status="paid" and sale_status = "completed" and DATE_FORMAT(receipt_date,"%Y-%m-%d") = ?',today)
-            .group("date_format(receipt_date, '%I %p')")
   end
 
   def self.employee_sales(today)