was listening to this Excellent Podcast about Minerva, basically Airbnb went and built a Metrics Store which is a central tool that hold all Measures and dimensions, the idea is to have one source of truth.
The Podcast is very insightful and worth listening to, But I was very surprised that none of the participants mentioned how existent BI vendors tried to solve the same Problem ,they talked Quickly about LookML but as far as I know it is not available yet for third party tools
Metrics Store is not new, it is just another name for Semantic Model, Business Objects had one from 30 years ago.
So Just for fun, and I am not sure if it is even practical, I wanted to test if PowerBI can act like a pure Metrics Store for third party tools.
I am using BigQuery as a data source, 1 fact table 80 Million records and 5 dimension Tables all using Direct Query Mode, PowerBI is not holding any data, all it does , it receive Queries from the Viz tool in this case Excel and Tableau and translated it to SQL and serve the results back.
I publish the Model to PowerBI service, here is the catch it has to be Premium workspace, Premium per user works too
now Using Tableau, I connect to SSAS, I get the server address from Workspace setting, notice PowerBI and SSAS are using the same engine.
and Voila Tableau Indeed Work just fine
now trying Excel
and here the SQL Queries generated by PowerBI
Notice here Tableau/Excel talk to PBI Semantic Model using MDX, which you can see here using DAX Studio where I can capture all the Queries coming to PBI
The Performance is not great but tolerable I guess, MDX Queries render from 6 to 10 seconds, But it did work which is rather amazing by itself 🙂
Metrics Store is an interesting idea on paper, but not sure in practice, it is hard to justify paying for multiple tools, if you build your semantic Model in one tool, why pay for another BI tool ? The Other challenge is self service Scenario, the user needs to be able to add extra Measures and Dimensions.
and for new vendors, it will be helpful to explain what kind of problems they are trying to solve that the existing tools couldn’t, just creating a new fancy name is not good enough.