diff --git a/controllers/admin/AdminProductsController.php b/controllers/admin/AdminProductsController.php
index af51d577b..4bd05ce3c 100644
--- a/controllers/admin/AdminProductsController.php
+++ b/controllers/admin/AdminProductsController.php
@@ -2441,21 +2441,21 @@ class AdminProductsControllerCore extends AdminController
 			{
 				$params = explode('_', $key);
 
-				$wpl_id = WarehouseProductLocation::getIdByProductAndWarehouse($params[1], $params[2], $params[0]);
+				$wpl_id = (int)WarehouseProductLocation::getIdByProductAndWarehouse((int)$params[1], (int)$params[2], (int)$params[0]);
 
 				if (empty($wpl_id))
 				{
 					//create new record
 					$warehouse_location_entity = new WarehouseProductLocation();
-					$warehouse_location_entity->id_product = $params[1];
-					$warehouse_location_entity->id_product_attribute = $params[2];
-					$warehouse_location_entity->id_warehouse = $params[0];
+					$warehouse_location_entity->id_product = (int)$params[1];
+					$warehouse_location_entity->id_product_attribute = (int)$params[2];
+					$warehouse_location_entity->id_warehouse = (int)$params[0];
 					$warehouse_location_entity->location = pSQL($location);
 					$warehouse_location_entity->save();
 				}
 				else
 				{
-					$warehouse_location_entity = new WarehouseProductLocation($wpl_id);
+					$warehouse_location_entity = new WarehouseProductLocation((int)$wpl_id);
 
 					$location = pSQL($location);
 
@@ -2464,10 +2464,8 @@ class AdminProductsControllerCore extends AdminController
 						$warehouse_location_entity->location = pSQL($location);
 						$warehouse_location_entity->update();
 					}
-					break;
 				}
 			}
-
 			$this->confirmations[] = $this->l('Warehouses and location(s) of the product have been updated');
 		}
 	}
diff --git a/controllers/admin/AdminStockCoverController.php b/controllers/admin/AdminStockCoverController.php
index d6fe6495c..ec5c5e3fe 100644
--- a/controllers/admin/AdminStockCoverController.php
+++ b/controllers/admin/AdminStockCoverController.php
@@ -159,7 +159,12 @@ class AdminStockCoverControllerCore extends AdminController
 				else // infinity
 					$data['coverage'] = '--';
 
-				$data['qty_sold'] = $this->getQuantitySold($data['id_product'], $data['id'], $this->getCurrentCoveragePeriod());
+				// computes quantity sold
+				$qty_sold = $this->getQuantitySold($data['id_product'], $data['id'], $this->getCurrentCoveragePeriod());
+				if (!$qty_sold)
+					$data['qty_sold'] = '--';
+				else
+					$data['qty_sold'] = $qty_sold;
 			}
 
 			echo Tools::jsonEncode(array('data'=> $datas, 'fields_display' => $this->fieldsDisplay));
@@ -236,7 +241,11 @@ class AdminStockCoverControllerCore extends AdminController
 					$item['coverage'] = '--';
 
 				// computes quantity sold
-				$item['qty_sold'] = $this->getQuantitySold($item['id'], 0, $this->getCurrentCoveragePeriod());
+				$qty_sold = $this->getQuantitySold($item['id'], 0, $this->getCurrentCoveragePeriod());
+				if (!$qty_sold)
+					$item['qty_sold'] = '--';
+				else
+					$item['qty_sold'] = $qty_sold;
 
 				// removes 'details' action on products without attributes
 				$this->addRowActionSkipList('details', array($item['id']));