public function getProducts()
 {
     $this->_db->setTable('products');
     $products = $this->_db->find('', 'all', 'product_name');
     foreach ($products as $product) {
         $objProduct = new Product($this->_db);
         $objProduct->product_id = $product->product_id;
         $types = $objProduct->getTypes();
         $product->types = $types;
         $productDetail[] = $product;
     }
     return $productDetail;
 }