Need Help Making a Date Slicer Ignore Flagged Rows

Hi MLUM 

Please try this:
For better testing, I did some change to the data which you provided, here's the sample data:
Table:

Then add a calculated table:

Table 2 = FILTER(
		VALUES('Table'[Date]),
		'Table'[Date] <> BLANK()
	)

Next, create a measure:

_Flag =
VAR _Slicer =
    VALUES ( 'Table 2'[Date] )
RETURN
    IF (
        ISBLANK ( SELECTEDVALUE ( 'Table'[Date] ) ),
        1,
        IF ( SELECTEDVALUE ( 'Table'[Date] ) IN _Slicer, 0 )
    )

Finally, create a slicer with the field Table 2[Date] and replace the Table[Flag] with the measure[_Flag] in the table visual, the result is as follow:

Best Regards

Zhengdong Xu
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