The WHERE condition of an SQL statement has two counterparts in DAX: FILTER and CALCULATETABLE. In this article we explore the differences between them, providing a few best practices in their use.  Read more

The DIVIDE function in DAX is usually faster to avoid division-by-zero errors than the simple division operator. However, there are exceptions to this rule, described in this article through a simple performance analysis.  Read more

Computing the rolling 12-months average in DAX looks simple, but it hides some level of complexity. This article explains how to write the best possible formula and how to avoid common pitfalls using time intelligence functions.  Read more

In DAX there are different ways to test whether a table is empty. This test can be used in complex DAX expressions and this short article briefly discuss what are the suggested approaches from a performance perspective.  Read more

A common best practice is to use CALCULATETABLE instead of FILTER for performance reasons. This article explores the reasons why and explains when FILTER might be better than CALCULATETABLE.  Read more

How do you get the last process date for an SSAS Tabular Database? This article shows the techniques you can use and explains how to interpret the information available.  Read more

Creating a hierarchy in a Power Pivot or Tabular data model is very easy, but you might experience performance issues if the hierarchy is not “natural”. This article explains how to create hierarchies avoiding these problems.  Read more

Values such as inventory and balance account, usually calculated from a snapshot table, require the use of semi-additive measures. In Multidimensional you have specific aggregation types, like LastChild and LastNonEmpty. In PowerPivot and Tabular you use DAX, which is flexible…  Read more

In a Power Pivot or Tabular model with inactive relationships, one can rely on the USERELATIONSHIP function to apply an inactive relationship to a particular DAX expression. Its usage is simple in a measure, but one might consider alternative syntax…  Read more

In the traditional star schema design of a Data Mart, you replace a missing, unknown or wrong date in the fact table with a dummy value in the Date dimension table. In Tabular, handling a Date table requires an existing…  Read more