<?php
defined('BASEPATH') OR exit('No direct script access allowed');

class Migration_Add_purchase_down_payment extends CI_Migration
{
 public function up()
 {
  if(!$this->db->field_exists('down_payment_required','purchase_orders'))
   $this->db->query("ALTER TABLE purchase_orders ADD down_payment_required TINYINT(1) NOT NULL DEFAULT 0 AFTER payment_plan");
  if(!$this->db->field_exists('down_payment_amount','purchase_orders'))
   $this->db->query("ALTER TABLE purchase_orders ADD down_payment_amount DECIMAL(18,2) NOT NULL DEFAULT 0 AFTER down_payment_required");
 }

 public function down()
 {
  if($this->db->field_exists('down_payment_amount','purchase_orders'))$this->db->query('ALTER TABLE purchase_orders DROP COLUMN down_payment_amount');
  if($this->db->field_exists('down_payment_required','purchase_orders'))$this->db->query('ALTER TABLE purchase_orders DROP COLUMN down_payment_required');
 }
}