Why the RLS bitmap default just went up 4x
Row-level security quietly switches strategies once a table gets big enough. A recent default change moves that line from 128K rows to 512K, and the reason it is not 2 million is a nice bit of engineering.
Category: Performance
The Impact of Primary Keys on DAX Query Performance in Power BI
When writing DAX queries, performance tuning often comes down to small design decisions that have big consequences. One such decision is whether to include Primary Key columns from Dimension tables in your SUMMARIZECOLUMNS statements. This is particularly important when those Dimension tables use DUAL or IMPORT storage modes. This article explains why doing so can … Continue reading The Impact of Primary Keys on DAX Query Performance in Power BI
How to Generate a DAXX File for Performance Tuning
When troubleshooting a slow DAX query, the right diagnostic bundle is worth a hundred screenshots. That bundle is a DAXX file, generated from DAX Studio. It captures the query, the server timings, the query plan, and a VertiPaq Analyzer snapshot of your model, all in one package, and without any of your actual query results. Perfect … Continue reading How to Generate a DAXX File for Performance Tuning
Direct Lake Performance Gets a Boost: Faster Join Index Creation
If you’ve been working with Direct Lake in Microsoft Fabric, you’ll know its magic resides in its ability to quickly load data. It loads data into semantic models from OneLake when needed. This feature eliminates the overhead of importing. But until recently, the first query on a cold cache might feel sluggish. Why? One reason … Continue reading Direct Lake Performance Gets a Boost: Faster Join Index Creation