I am new in my company, my manager ask me about the possibility of displaying attendance data for each employee in SharePoint online!
How can show data from the SAP system in SharePoint online?
Is SharePoint online suitable for intranet?
This post deals with a similar type of question. At work, we have SP 2013, but we import 'external data' from other systems - like you wish to do with SAP. In SP 2013 there is a List type called 'External List'.
These are only high-level steps, you'll need to work out the details.
What you will still need to do is create a mechanism to keep your SAP list refreshed with new/modified data from your SAP system. Possibly Windows Task Manager and PowerShell could do this. Possibly a Sharepoint Designer Workflow could then be configured on your SAP List; when an item is created/modified on the SAP List -> run workflow to create/modify items in your native SP List.
This is the only method I know about, others will hopefully have other suggestions for you too!
I agree with the answer Tally provided as the solution, however it would seem that in your case simply purchasing an SAP integration system from a third party provider may be the preferred option