XML for Analysis was defined back in 2001 as a standard way to access and manage analytic systems. A good metaphor for XMLA is its cousin SQL – SQL is a standard approach in relational systems for both querying and defining relational objects. Like SQL, XMLA is that but for analytical systems. (Well, almost. More about this later).
The ball for XMLA got rolling quickly after it was defined with several companies jumping on board. Hyperion (since acquired by Oracle) supports XMLA for Essbase, SAP HANA has support , and Mondrian supports it as well.
XMLA is different from SQL in that it is a low-level protocol and it’s not that common to be used explicitly. Creating a table with SQL can be done very easily – creating a model with XMLA was never intended to be done by hand. Instead XMLA is wrapped up inside client libraries that developers manipulate. They may not know what is going on behind the scenes, but whenever a developer uses adomd.net, AMO, or Analysis Services OLEDB provider it’s XMLA that is being emitted.
Ok – enough about what it is. Why should you care?
XMLA is in the news today because Power BI announced support for the protocol, provided an endpoint to connect to, and, with that support, the same client libraries now work with Power BI Premium the same way they work with SQL Server Analysis Services or Azure Analysis Services.
Until this announcement, you could communicate with Power BI with the tools built for and dedicated to Power BI – Power BI Desktop, Power BI REST APIs, and the powershell cmdlets. Now that the XMLA endpoint has been released and Power BI is backwards compatible with Analysis Services, the same tooling that works with Analysis Services now works with Power BI. This includes (but not limited to!) SQL Server Management Studio, Visual Studio (with the Analysis Services Projects Extension), SQL Server Data Tools, and SQL Server Profiler.
Third party BI applications that can connect to Analysis Services can now connect to Power BI Premium. So Tableau, for example, now can connect to Power BI as well.
And third party management tools can now be used for authoring Power BI Premium models. Tabular Editor and Dax Studio are preferred tools for many BI developers – now these can be used with Power BI Premium as well.
So you might care about XMLA because it makes Power BI to be on par with Analysis Services with respect to the client and management tools it supports.