by Chris Webb | Dec 3, 2023 | Chris Webb
Power Query allows you to merge (“join” in database terms) two tables together in a variety of different ways, including left and right anti joins. Unfortunately, as I found recently, anti joins don’t fold on SQL Server-related data sources, which can result in...
by Chris Webb | Nov 26, 2023 | Chris Webb
A lot of DAX performance problems relate to the use of strict and eager evaluation with the IF or SWITCH functions. It’s an incredibly complex, “it depends”, black-box type of topic and naturally Marco and Alberto have a great article on it here. Rather than describe...
by Chris Webb | Nov 18, 2023 | Chris Webb
Last week it was announced that Power BI datasets have been renamed: they are now semantic models. You can read the announcement blog post here and see the change in the Fabric/Power BI UI already. The name change proved to be surprisingly uncontroversial. Of course...
by Chris Webb | Nov 12, 2023 | Chris Webb
Excel workbooks are one of the slowest data sources you can use with Power Query in Excel or Power BI. Reading small amounts of data from small workbooks is usually fast; reading large amounts of data from large workbooks can be very slow. But what about reading small...
by Chris Webb | Nov 5, 2023 | Chris Webb
Recently I was involved in an interesting discussion on Twitter X about how partitioning a table in a Power BI dataset semantic model can affect compression and therefore its size and query performance. You can read the thread here. It got me thinking: is there a way...
by Chris Webb | Oct 29, 2023 | Chris Webb
If you’re a fan of using Log Analytics for monitoring Power BI activity, then you may have noticed there’s some new data in the ApplicationContext column of the PowerBIDatasetsWorkspace table. Up until recently the ApplicationContext column only contained IDs that...
