Earlier this month we added some features that lay the foundation for Office 365 experience and connectivity in Data Explorer. From now on, you will be able to consume documents hosted in SharePoint Online using one of the following mechanisms:
- If you know the URL to the document that you would like to access, you can directly import it using the Web Content option in the Add Data page. When prompted for credentials after specifying the URL to the document, you can provide your Microsoft Online Services ID as the credentials to access the document (which you can specify to be applied to the entire SharePoint site).

- Alternatively if you want to navigate the SharePoint documents library to see the list of documents in the SharePoint site, you can add a Formula resource and call the SharePoint.Contents(“Your SharePoint site URL”) library function, this will return the top-level contents of the SharePoint site as displayed in the following screenshot.

From this preview, clicking the Content column icon you can navigate to the desired document. In the screenshot below, we navigated to an Excel workbook under the “Shared Documents” folder and previewed the “Categories” worksheet.

In upcoming weeks and months, expect to see a more integrated user experience for navigating a SharePoint site and browsing its contents. We already support full graphical user interface access to a SharePoint’s site feed via the SharePoint item in the Add Data page, both for on-premises and SharePoint Online deployments – which means that you do not need to start off with the SharePoint.Contents() function call directly on the formula bar in this case.
Source : http://blogs.msdn.com/b/dataexplorer/