Variable Concatenation for Key?

Hi, jcawley 

Based on your description, i created data to reproduce your scenairo. The pbix file is attached in the end,

Appointment:

Sales:

You may create a calculated column or a measure as below.

Calculated column:

Column = 
var c = 
COALESCE(
    COUNTROWS(
        FILTER(
            ALL(Sales),
            [Patient_ID]=EARLIER(Appointment[Patient_ID])&&
            ABS([Purchase_Date]-[Appt_Date])<=3
        )
    ),0
)
return
IF(
    c=0,
    FALSE(),
    TRUE()
)

Measure:

Measure = 
var c = 
COALESCE(
    COUNTROWS(
        FILTER(
            ALL(Sales),
            [Patient_ID]=MAX(Appointment[Patient_ID])&&
            ABS([Purchase_Date]-MAX(Appointment[Appt_Date]))<=3
        )
    ),0
)
return
IF(
    c=0,
    FALSE(),
    TRUE()
)

Result:

Best Regards

Allan

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