Advance your Data & AI career with 50 days of live learning, dataviz contests, hands-on challenges, study groups & certifications and more!
Get registeredGet Fabric Certified for FREE during Fabric Data Days. Don't miss your chance! Request now
Data table linked to a Key and Date Dimension:

I want to calculate a 1 the first time a Patient ID appears per service date.
If a Patient ID appears multiple times on a particular service date, I only want to calculate a 1 the first time it appears.
Is there an easy way to do this as a calculated column?
Solved! Go to Solution.
I ended up concatenating Pat_ID and Orig_Service_Date and then doing a Distinct Count of that
I ended up concatenating Pat_ID and Orig_Service_Date and then doing a Distinct Count of that
You should probably do this as a measure and not a column. Here is one way to do it, if I understand your scenario correctly.
Unique Visits = COUNTROWS(SUMMARIZE(Data, Data[Pat_ID], Data[Orig_Serv_Date]))
Pat
To learn more about Power BI, follow me on Twitter or subscribe on YouTube.
Can't be a measure.
Must be a calculated column as there are about 10 other columns not shown that the # has to interact with.
Advance your Data & AI career with 50 days of live learning, contests, hands-on challenges, study groups & certifications and more!
Check out the October 2025 Power BI update to learn about new features.