PowerBI - Choosing a relative field between 2 dates

Hi tchooper7 ,

Please try using DAX to create the new column.

Name = 
CALCULATE (
    MAX ( 'Table 2'[Name] ),
    FILTER (
        'Table 2',
        'Table 2'[Date] >= EARLIER ( 'Table 1'[Start Date] )
            && OR (
                'Table 2'[Date] <= EARLIER ( 'Table 1'[End Date] ),
                'Table 1'[End Date] = BLANK ()
            )
    )
)

Or create custom column in Power Query.

= let 
  s = [Start Date], e = [End Date]
in
  Table.SelectRows(#"Table 2", each [Date] >= s and ([Date] <= e or e = null)){0}[Name]

If the problem is still not resolved, please provide detailed error information or the expected result you expect. Let me know immediately, looking forward to your reply.
Best Regards,
Winniz
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