Modern Semantic Model Testing with DAX, UDFs, and AI

Title: Modern Semantic Model Testing with DAX, UDFs, and AI

Presentation by: John Kerski
Date: April 6, 2026
Time: 6:30pm – 7:45pm
Format: This month our meeting is Online only

Teams Meeting Link: https://teams.microsoft.com/meet/23853260920720?p=kbd0LFp81BxGyjfom8

Description: Too many teams still rely on a “publish and pray” approach in Power BI. Changes are made to Power Query, DAX, or refresh logic, and teams simply hope nothing breaks. If we are serious about adopting a DataOps mindset where quality is paramount, this approach is no longer acceptable.
As analytics solutions scale and newer contributors get involved, automated validation becomes critical. Testing protects user trust by catching issues early and prevents the erosion of confidence that happens when the same production problems appear again and again. It also creates safety rails that allow junior or less experienced team members to contribute faster and more confidently without fear of breaking critical semantic models.
Testing semantic models has not always been easy in Power BI. However, the introduction of the DAX Query View opened the door to a practical and reusable testing pattern. Building on that foundation, User Defined Functions now allow us to standardize common tests across projects and teams.

In this session, I will walk through the DAX Query View testing pattern, explain how User Defined Functions fit into that approach, and introduce PQL.Assert, an open-source library of reusable DAX assertions. Assert-style testing is a familiar concept in software engineering, where you explicitly validate that a condition is true and fail the test when it is not. PQL.Assert brings this concept to Power BI semantic models, helping teams standardize tests, promote reuse, and even leverage AI to assist with test creation and execution.
By the end of this session, you will see how to move beyond “publish and pray” and start delivering Power BI semantic models with confidence.

Bio:

#### John Kerski

John leverages his 10+ years of technical and government leadership experience to help Federal Agencies, and private sector clients utilize Microsoft products to their fullest potential. His certifications with Microsoft products offers customers a high rate of return when looking to invest in Microsoft solutions.