Join us at FabCon Atlanta from March 16 - 20, 2026, for the ultimate Fabric, Power BI, AI and SQL community-led event. Save $200 with code FABCOMM.
Register now!To celebrate FabCon Vienna, we are offering 50% off select exams. Ends October 3rd. Request your discount now.
In Power BI Desktop I'm attempting to dynamically determine the last instance of a character and SUBSTITUTE that character with another. The following DAX formula appears to work in Excel but does not work in Power BI Desktop.
Column1 = test1_test2_test3
Formula: Last_Replaced = Last_Replaced = SUBSTITUTE(table1[Column1],"_","@",LEN(table1[Column1])-LEN(SUBSTITUTE(table1[Column1],"_","")))
This returns "An argument of function 'SUBSTITUTE has the wrong data type or has an invalid value."
However, if I set the number to 2 in the forumla it works.
If I first create a column that determines the value and holds this then include that new column in the formula it fails with the same error.
Is this by design, a bug, or is there another way to accomplish what I'm trying to do in Power BI Desktop?
Thank you,
Trav
Solved! Go to Solution.
Replace your underscore "_" with a pipe "|" and use the PATH functions.
Replace your underscore "_" with a pipe "|" and use the PATH functions.