Filter table using date slicer, then filter dates in another table based on results

Hi WBscooby ,

Please create a new measure and use it as visual's filter.

Measure = 
CALCULATE (
    COUNTROWS ( 'SchoolAttendance' ),
    TREATAS (
        DISTINCT ( 'Intervention'[Customer ID] ),
        'SchoolAttendance'[Customer ID]
    ),
    FILTER (
        'SchoolAttendance',
        'SchoolAttendance'[Attendance Start Date]
            <= CALCULATE (
                MAX ( 'Intervention'[Int End Date] ),
                RELATEDTABLE ( 'Intervention' )
            )
            && 'SchoolAttendance'[Attendance End Date]
                >= CALCULATE (
                    MAX ( 'Intervention'[Int End Date] ),
                    RELATEDTABLE ( 'Intervention' )
                )
    )
)

Best Regards,
Gao
Community Support Team

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