Forum Discussion
How is a function speed determined in both DAX and Power Query
Hello All, Often when I am browsing various Power BI blogs/forums I will see posts that this or that function is a slow function as it scans every line. Filter is often brought up in discussions ...
A lot of that comes with experience. For example, any function with an extra "X" on the end is generally a "slow" function as it is essentially doing a table scan. For example, MAXX, COUNTX, MINX, SUMX, etc.
Greg_Deckler
Community Champion
Community ChampionA lot of that comes with experience. For example, any function with an extra "X" on the end is generally a "slow" function as it is essentially doing a table scan. For example, MAXX, COUNTX, MINX, SUMX, etc.
Thanks for your reply, is there anyway to see the underlying code for either DAX or power query functions or is this all closed?
- Greg_Deckler
Check out some of these DAX tools, they may help:
https://www.sqlbi.com/articles/tools-for-dax-and-tabular-developers/