DAX calculations can leverage relationships present in the data model, but you can obtain the same result without physical relationships, applying equivalent filters using specific DAX patterns. This article show a more efficient technique to apply virtual relationships in DAX expressions.
Writing measures referencing other measures is in general a good idea that simplifies the DAX code, but you might face specific bottlenecks. This article describes which performance issues might arise when different measures aggregate the same column using different filter arguments, and how to improve efficiency of your DAX code.
The new DAX available in Excel 2016 and the data model in Power BI and Analysis Services 2016 offer tools to manage many-to-many relationships in a more efficient way than previous version, as described in this article.
A data model for DAX has three numeric data types: integer, floating point, and fixed decimal number. This article describes them and explains why the fixed decimal number should be used instead of the floating point in most scenarios.
When you create a data model in Power BI, you should consider how to properly use naming convention and what columns to include, in order to improve usability and performance. This article provides a quick list of best practices valid for both Power BI and Power Pivot.
DAX introduced a GROUPBY function that should replace SUMMARIZE in some scenarios. This article describes how to use GROUPBY in nested grouping scenarios and other improvements.
You can create static tables in DAX using the DATATABLE function. This article describes the syntax of this new feature and shows when and how to use it.
When you apply a multiple selection to a slicer or to a filter, you obtain a logical OR condition between selected items. This article shows how to implement a logical AND condition in a measure instead of the standard OR one.
One of the first concepts to learn in DAX is the difference between calculated columns and measures. This article shortly recap the differences and describes when to use each one.