The Power Of Dual Storage Mode For Power BI Aggregations

Reza Rad continues a series on Power BI aggregations by explaining how using the Dual storage mode can make queries faster if you use both Import and DirectQuery sources:

This is not what we actually expect to see. The whole purpose of Sales Agg table is to speed up the process from DirectQuery mode, but we are still querying the DimDate from the database. So, what is the solution? Do we change the storage mode of DimDate to Import? If we do that, then what about the connection between DimDate and FactInternetSales? We want that connection to work as DirectQuery of course.

Now that you learned about the challenge, is a good time to talk about the third storage mode; Dual.

Read on for an example-filled tutorial.