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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
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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.
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