Как добавить мою sql логику в этот код?

 if ($query->num_rows) {
        $cid = (int)$this->customer->getId();
        $pid = (int)$query->row['product_id'];
    if($cid>'0' ) {
    $pppo = $this->db->query("SELECT op.quantity FROM oc_order_product AS op LEFT JOIN oc_order AS o ON o.order_id=op.order_id WHERE o.customer_id='".$cid."' AND product_id = '" . (int)$pid . "' ");
if(isset($pppo->row['quantity']) AND !empty($pppo->row['quantity']) AND $pppo->row['quantity']>'0') {
$nqty = $pppo->row['quantity'];
} else {
$nqty = '0';
}
$ppp = $this->db->query("SELECT isbn, jan FROM " . DB_PREFIX . "product WHERE product_id = '" . (int)$query->row['product_id'] . "'  LIMIT 1");
                    $iss = $query->row['isbn'];
                    $jan = $query->row['jan'];
                    $jjan = (int)$jan-(int)$nqty;
if($jjan>'0') {
            //  if($cart['quantity']<$jjan) {

$ppp = $this->db->query("SELECT isbn, jan FROM " . DB_PREFIX . "product WHERE product_id = '" . (int)$query->row['product_id'] . "'  LIMIT 1");
                    $iss = $query->row['isbn'];
                    if($iss>'0') {
                        $price = $query->row['price']-$query->row['price']/100*$iss;
                    } else {
                        $price = $query->row['price'];
                    }
}
}
} else {
    $ppp = $this->db->query("SELECT isbn, jan FROM " . DB_PREFIX . "product WHERE product_id = '" . (int)$query->row['product_id'] . "'  LIMIT 1");
                    $iss = $query->row['isbn'];
                    $jan = $query->row['jan'];
if($jan>'0') {
            //  if($cart['quantity']<$jan) {

                //  $pp = $this->model_catalog_product->getProduct($query->row['product_id']);
                $ppp = $this->db->query("SELECT isbn, jan FROM " . DB_PREFIX . "product WHERE product_id = '" . (int)$query->row['product_id'] . "'  LIMIT 1");
                    $iss = $query->row['isbn'];
                    if($iss>'0') {
                        $price = $query->row['price']-$query->row['price']/100*$iss;
                //      $nprice = $product['price']/100*40;
                    } else {
                //      $nprice = $product['price']/100*40;
                        $price = $query->row['price'];
                    }
            //  }
}
} 
if(empty($price)) {
    $price = (int)$query->row['price']-(int)$query->row['price']/100*(int)$query->row['isbn'];
//  $price = (int)$query->row['price'];
}
        //  $price = (int)$query->row['price']-(int)$query->row['price']/100*(int)$query->row['isbn'];
        //  $price = (int)$query->row['price'];
            return array(
                'product_id'       => $query->row['product_id'],
                'name'             => $query->row['name'],
                'description'      => $query->row['description'],
                'meta_title'       => $query->row['meta_title'],
                'meta_h1'          => $query->row['meta_h1'],
                'meta_description' => $query->row['meta_description'],
                'meta_keyword'     => $query->row['meta_keyword'],
                'tag'              => $query->row['tag'],
                'model'            => $query->row['model'],
                'sku'              => $query->row['sku'],
                'upc'              => $query->row['upc'],
                'ean'              => $query->row['ean'],
                'jan'              => $query->row['jan'],
                'isbn'             => $query->row['isbn'],
                'mpn'              => $query->row['mpn'],
                'location'         => $query->row['location'],
                'quantity'         => $query->row['quantity'],
                'stock_status'     => $query->row['stock_status'],
                'image'            => $query->row['image'],
                'manufacturer_id'  => $query->row['manufacturer_id'],
                'manufacturer'     => $query->row['manufacturer'],
                'price'            => ($query->row['discount'] ? $query->row['discount'] : $price),
                'special'          => $query->row['special'],
                'reward'           => $query->row['reward'],
                'points'           => $query->row['points'],
                'tax_class_id'     => $query->row['tax_class_id'],
                'date_available'   => $query->row['date_available'],
                'weight'           => $query->row['weight'],
                'weight_class_id'  => $query->row['weight_class_id'],
                'length'           => $query->row['length'],
                'width'            => $query->row['width'],
                'height'           => $query->row['height'],
                'length_class_id'  => $query->row['length_class_id'],
                'subtract'         => $query->row['subtract'],
                'rating'           => round($query->row['rating']),
                'reviews'          => $query->row['reviews'] ? $query->row['reviews'] : 0,
                'minimum'          => $query->row['minimum'],
                'sort_order'       => $query->row['sort_order'],
                'status'           => $query->row['status'],
                'date_added'       => $query->row['date_added'],
                'date_modified'    => $query->row['date_modified'],
                'viewed'           => $query->row['viewed']
            );
        } else {
            return false;
        }
    }

Тут нужно проверку сделать product_id order_product_id customer_id
Если получается пользователь с customer_id = 1 купил уже этот товар на который каждому пользователю скидка на 2 шт по полям (isbn(%) jan(количество скидок) то ему больше не будет скидки то есть

     SET @customer = 1;
select tb03.customer_id, tb01.product_id, sum(tb01.quantity)
from oc_order_product tb01
left join oc_order tb02 ON tb01.order_id = tb02.order_id 
left join oc_customer tb03 ON tb02.customer_id = tb03.customer_id
where tb03.customer_id = @customer
group by tb03.customer_id, tb01.product_id

В конце сверяем по товару product_id и product_id(купленого товара) Если равно то нужно будет quantity(количество купленого товара) - jan(количество скидок на этот товар) и если = 0 то не будет скидки типа!
Как этот sql добавить в мой нынешний код?