Cross valiadation between two tables

Hi liapimentaa ，

If you need to check the upper and lower case of a word's letters, try a merge query in Power query:

then crate a new measure like:

Measure = IF(ISBLANK(COUNT(Table1[Column1.1])),"yellow")

and use it as a background condition:

If you don't need to check the case of letters, you can try this one:

Measure = 
VAR _cur_value = SELECTEDVALUE('Table1'[Column1])
VAR _count = CALCULATE(COUNTROWS('Table2'),'Table2'[Column1]=_cur_value)
VAR _result = IF(ISBLANK(_count),"yellow")
RETURN
_result

Best Regards,
Gao
Community Support Team

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If I misunderstand your needs or you still have problems on it, please feel free to let us know. Thanks a lot!

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