To view the invoice data on the related account records in sales force when invoices are stored in SAP we must:
Create an External Object connected to an invoice table in SAP
OR
Connect to an O-Data Publisher Service for SAP databases.
SAP can be defined as Systems, Applications and Products. SAP is basically a software which has a backbone of SAP ERP (most advance Enterprise Resource Planing). SAP software helps to manage many business areas by providing powerful tools that include financial and logistic areas.