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Find a duplicate by multiple columns and group of rows

Hi everyone,

I have a problem finding a proper dax measure for a specific type of duplicates in a fact table


Uploading a snippet with few dummy data and the image with formatted background for duplicates


What is my goal:

I need to find duplicate Import batches for Semi Octa - but duplicate condition is met only when all [Lia] values for each [Freq] in a batch are the same with another batch


for instance - Serial number 190092PL has 2 duplicate batches :

ImportbatchID - 190092PL_1 and 190092PL_91 - same [lia] values for all frequencies  (50,100,200) in a batch

190092PL_13 and 190092PL_1 - same lia for freq 50,100, there is no 200 freq in that import batch


190092PL190092PL_11wert1Semi Octa5044,9888
190092PL190092PL_11wert1Semi Octa10099,0903
190092PL190092PL_11wert1Semi Octa20034,9983
190092PL190092PL_81Qa89Semi Octa5043,90432
190092PL190092PL_92OP09eSemi Octa5021,434
190092PL190092PL_92OP09eSemi Octa10045,9034
190092PL190092PL_92OP09eSemi Octa2007483,8933
190092PL190092PL_132Xt56Semi Octa5021,73773
190092PL190092PL_132Xt56Semi Octa10056,98322
190092PL190092PL_912tr452wSemi Octa20034,9983
190092PL190092PL_171 Semi Octa10021,32
190092PL190092PL_171 Semi Octa20031,123
190092PL190092PL_171 Semi Octa5044,9888
190092PL190092PL_911tr452wSemi Octa10099,0903
190092PL190092PL_921wsx73Semi Octa20059,09815
190092PL190092PL_911tr452wSemi Octa5044,9888
190092PL190092PL_152cj9Semi Octa5021,73773
190092PL190092PL_152cj9Semi Octa10056,98322
9930PL329930PL32_341wrr23Semi Octa5044,93
9930PL329930PL32_341wrr23Semi Octa10045,932
9930PL329930PL32_341wrr23Semi Octa20071,093
9930PL329930PL32_441fd42Semi Octa10045,932
9930PL329930PL32_342 1 Octa10054,32
9930PL329930PL32_342 1 Octa5022,23
9930PL329930PL32_633 Semi Octa5045,65
9930PL329930PL32_633 Semi Octa10032,43
9930PL329930PL32_491 Semi Octa20059,09815
9930PL329930PL32_204 Semi Octa5044,9821103
9930PL329930PL32_204 Semi Octa10040,09921
9930PL329930PL32_204 Semi Octa20022,01101
9930PL329930PL32_195 Semi Octa5032,42332
9930PL329930PL32_195 Semi Octa1002,90019013
9930PL329930PL32_441fd42Semi Octa5044,93
9930PL329930PL32_441fd42Semi Octa20071,093




i used a measure with distinctcount[lia]  - count[lia] to compare the values, but i dont know how to use it for group of frequencies

Does anyone have any idea?


Super User
Super User

Hi @MattReckoner ,

Is this correct understanding:
If Serial_Number and Frequency and Lia is the same and there is any second ImportbatchID for this combination, then this is a duplicate, right?
Any third, fourth, fifth, ... ImportbatchID is another duplicate?
Then this is what you need:
- Group by Serial_Number, Freq, Lia
- For each distinct combination of above, count occurences
- If there is more than one occurence, these are duplicates


Count of duplicate batches = 
VAR _DuplicatesPerSerialNumberFrequencyLia =
        // Group by Serial_Number, Freq, Lia
        // For each distinct combination of above, count occurences
        VAR _CountOfBatch = CALCULATE ( COUNTROWS ( 'Table' ) )
        // If there is more than one occurence, these are duplicates
        IF (
            _CountOfBatch > 1,
            _CountOfBatch - 1 // each first instance is not a duplicate
// Return total number of duplicates in current context
SUMX ( _DuplicatesPerSerialNumberFrequencyLia, [@CountOfDuplicates] )


This measure produces this result from your sample data:

Duplicate batchesDuplicate batches




Hi Martin_D


Thanks for reply! its not exactly what i wanted

As your dax finds duplicates for each frequency separately. 

I've created a measure with virtual table where i pivoted freq column. Made columns freq_50, freq_100, freq_200 and created uniqueKey as a combination of serial numer & freq_50 & freq_100 & freq_200 & lia rest is similar, countows and sumx. 


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