ItemNo ItemName ItemQty GroupName
     234       item1     2      Group1
     235       item2     4      Group2

var result = context.Batch.Where(i => i.Item_No ==   "235").First();

            result.ItemQty = 10;
            context.UpdateObject(result);
            context.SaveChanges();

Error : <?xml version="1.0" encoding="utf-8"?><m:error xmlns:m="http://schemas.microsoft.com/ado/2007/08/dataservices/metadata"><m:code /><m:message xml:lang="en-US">**An error occurred while processing this request**.</m:message><m:innererror><m:message>**The underlying application page is not editable.**</m:message><m:type>Microsoft.Dynamics.Nav.Service.ODataServiceProvider.ODataException</m:type><m:stacktrace></m:stacktrace></m:innererror></m:error>