Need help retrieve data on two data set

Hi FranckGbadamass 

If you want to use matrix to display the count, you can take the method mentioned by AlexisOlson, it's the fastest way. 

If you don't want to use matrix or you just want to know how to calculate the count by DAX, try measures bellow,

code A = 
    var  _t0=SUMMARIZE(FILTER(ALL(Table2),Table2[Rules]=MIN(Table2[Rules])),[File ID])
    var  _t1=SUMMARIZE(FILTER(ALL(Table1),Table1[Decision code] ="A"),[File ID])
    var  _t2=INTERSECT(_t1,_t0)
return COUNTROWS(_t2)

code R = 
    var  _t0=SUMMARIZE(FILTER(ALL(Table2),Table2[Rules]=MIN(Table2[Rules])),[File ID])
    var  _t1=SUMMARIZE(FILTER(ALL(Table1),Table1[Decision code] ="R"),[File ID])
    var  _t2=INTERSECT(_t1,_t0)
return COUNTROWS(_t2)

result

Best Regards,

Community Support Team _Tang

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