One of the announcements made at the Microsoft Data Summit in this past March 2016 was the availability of Analyze in Excel. This feature allows an Excel workbook to connect to a data model that is stored in the Power BI service, and to use it to analyze the data contained within. With this approach Excel is not importing data, or at least it is not importing any more data than the query results. It is exactly like connecting data to SQL Server Analysis Services data sources, something that Excel users have been doing for years. Well, to be completely accurate, it’s not LIKE connecting to SSAS, it IS connecting to SSAS. The only difference is that in this case SSAS is in the cloud. This feature significantly enhances the utility of the Power BI Service, and is important for several reasons that may not be all that obvious. I’d like to walk through a few of them, but let’s start with the obvious.
Excel is a very powerful analytical tool
As nice, and as attractive as Power BI visuals are, Excel still rules the roost when it comes to doing advanced analytics. Excel has been doing this for years and is very mature. It supports features such as pivot tables, pivot charts, and drill through to data, where Power BI reports still do not. The lack of these features can be a blocker for Power BI on its own, but if the data models in Power BI can be analyzed with Excel, suddenly a move to Power BI is not an either/or decision – you can have it both ways. You can deploy models and reports into Power BI and take advantage of all the goodness there, but you can also connect with Excel when the deep analysis is needed. With Analyze in Excel, you can have it both ways.
A wider audience for your data models
Very often, the person that builds the data model is the same person that does the analysis. This is the nature of self-service analytics. In the past when the only multidimensional analysis tools were OLAP cubes and connected Excel workbooks, cube design was a specialized skill. The cubes were published and users would use them as is. The advent of the data model (Power Pivot) and self service analytics lowered the skills bar so that analysts could acquire data, model it and analyze it, making the entire process much quicker and responsive. However, this still puts the model out of reach for those with no data modeling skills or interest.
Analyze in Excel provides the best of both worlds. Analysts can build models and reports in Power BI, and users that need more in depth analysis can connect to them with Excel without having to reinvent the wheel. This in effect provides the same capability that PowerPivot for SharePoint does on premises. One model can now reach a much wider audience of users. This has many of the benefits of an on-premises SSAS deployments without all of the organizational overhead of getting them up and running.
Uses the Analysis Services OLEDB Driver
The connection that is made from Excel to the Power BI services uses the latest version of the classic Analysis Services OLEDB driver. This is the driver that has always been used to allow Excel (and other tools) to communicate with Analysis Services, and this new version has been updated in order to work with the cloud based SSAS service. In fact, in order to use the feature, you must first download and install the updated driver. Therefore, in theory, any tool that uses this driver should be able to communicate with Power BI models as if Power BI was one great big SQL Server Analysis Services server (because it is).
It really is Analysis Services in the cloud
The Power BI service itself is backed by tabular mode SSAS. Until now, it was necessary to go through the service to access it. Analyze in Excel is the first instance that I know of that a client application communicating directly with that SSAS instance. While this connection is really using the Power BI API, it does beg the question – can a fully Platform as a Service version of Analysis Services be very far away?
Claims based authentication and Power BI API
None of the products in the SQL Server suite currently supports claims authentication. This is true even for the yet unreleased SQL Server 2016. Even SQL Azure, a cloud based version of SQL Server, requires SQL authentication only (although Azure Active Directory authenticated databases are currently in preview). However, looking at the connection string contained in the ODC file used by the Analyze in Excel feature reveals some interesting things. Here’s one connection string:
<odc:ConnectionString>Provider=MSOLAP.7;Integrated Security=ClaimsToken;Identity Provider=AAD;Data Source=https://analysis.windows.net/powerbi/api;;Initial Catalog=xxxxxxx; ……..
The value MSOLAP.7 for the provider indicates that this is the next version of the SSAS OLEDB Driver. No surprises there, but this does hint at future compatibility (see SharePoint below). The value for Integrated Security, and Identity Provider (ClaimsToken and AAD) indicate that it is leveraging Azure Active Directory Claims authentication. We therefore have a version of SSAS that can use Claims based authentication. This isn’t available to on-premises installations, but given that the capability has been built, I imagine that it is not all that far away.
Finally, the Data source indicates that the Power BI API is being used to marshal all communication with the back end API service. I think that it is reasonably to conclude that any API for a PaaS based version of SSAS would be based on, or strongly resemble the Power BI API. They may even be one and the same.
Excel Online in SharePoint
As anyone that has set up PowerPivot for SharePoint can tell you, SharePoint supports the configuration of new OLEDB drivers. This support carries forward into the Office Online Server in the world of SharePoint 2016. Given that both SharePoint and OOS utilize claims based authentication, it should theoretically possible to create a workbook that uses the Analyze in Excel feature, store it in SharePoint, and have it work for multiple users from within a browser. I imagine that more plumbing is needed at this point, but it would be an interesting way of integrating Power BI in the cloud with SharePoint both on premises and Online.
Reusing the Excel Files, and Limitations
In the same vein as discussed with SharePoint, Power BI itself allows Excel files to be interacted with in the service in exactly the same manner that Excel Online does. Theoretically, one should be able to use Analyze in Excel to build a workbook, then connect it to Power BI and have it work for interaction. While it is possible to connect it, all interactions fail at the moment. It appears that the Power BI service (or the backing Office Online service) does not yet support the new OLEDB driver.
Another current limitation of this feature is that data sources using Direct Query (this includes SSAS sources) or sources created by the Power BI API cannot be used with Analyze in Excel. At least not yet.
Analyze in Excel is another useful tool in the Power BI arsenal, but as outlined above, I think that it’s a harbinger of even greater things to come.