Power BI Weekly

Issue #338 - 16th December 2025

Welcome to the 338th edition of Power BI Weekly! This will be the last edition of 2025 as I head on my holidays for the next couple of weeks. As ever, thank you for another year of your readership, and what a year it's been! While Fabric has taken away some of Power BI's limelight, we have certainly seen some impressive innovation on both fronts. This year, the "hardening" of Power BI files has all but been completed with PBIR soon becoming the default format, the TMDL view GA, the downloading of XMLA-edited files, web and desktop parity and so on. Naturally, GenAI has been at the forefront of most feature announcements across the industry this year, and Power BI and Fabric are no different with the advancements in Copilot, agentic features and MCP tools. All with the goal of improving your development, but your mileage may vary! If you'd like, you can read the official Power BI 2025 holiday recap: A decade of innovation and impact. Bring on 2026 and whatever that may bring. I dare say AI will continue playing a significant part!

So, onto the final set of highlighted articles in what's a pretty small edition. Marco Russo has written a couple of articles describing a couple of services/tools for your benefit: Introducing DAX Lib, the “app store” for DAX User-Defined Functions and Introducing DAX Optimizer Basic. And Chris Webb has again continued his series of helpful hints and tips on tuning Power BI Copilot performance with his article Power BI Copilot And Report Filters And Slicers.

Happy holidays everyone, and see you in the new year!