You can Add and Update OrderItems in your network by issuing a
POST request to http://api.resengo.com/WS/OrderItem.
The OrderItemIDs returned in the response should be saved in your database.
If possible, always use an OrderItemID when updating an OrderItem in the network.
If you do not have a OrderItemID yet (because you are uploading the OrderItem for the first time) and you are sending multiple OrderItems at once, you can differentiate between the results by specifying a SMS_OrderItemID or SMS_OrderItem for each posted OrderItem. These should correspond to the primary key of your local database.