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AbdulAzad
Frequent Visitor

Union not removing the duplicate data

Hi,

 

Looks like UNION DAX has a bug, its not removing the duplicate data, I tried to do union of two table by using the option to create a new table based on UNION DAX.

 

Union generally deletes duplicate data between two tables and union all keeps even the duplicate data. Here in Power BI desktop, I don't see the UNION is removing the duplicate data.

 

Can you guys please confirm, if it is a bug? If it is a bug then when can we expect the resolution?

 

Thanks & Regards,

Abdul

1 ACCEPTED SOLUTION
v-yalanwu-msft
Community Support
Community Support

Hi @AbdulAzad ,


Accoridng to the official document , UNION() returns a table that contains all the rows from each of the two table expressions.

v-yalanwu-msft_0-1619404461156.png

IF you want to union and remove the duplicate data, you can use “distinct() ”to achieve it. The following is an example::
26.jpg
The final output is shown below:  UNION() vs DISTINCT(UNION())
newtable1 = UNION('Table','Table (2)')      vs      newtable2 = DISTINCT(UNION('Table','Table (2)'))

v-yalanwu-msft_1-1619404533473.png

Best Regards,
Community Support Team_ Yalan Wu
If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.

View solution in original post

2 REPLIES 2
v-yalanwu-msft
Community Support
Community Support

Hi @AbdulAzad ,


Accoridng to the official document , UNION() returns a table that contains all the rows from each of the two table expressions.

v-yalanwu-msft_0-1619404461156.png

IF you want to union and remove the duplicate data, you can use “distinct() ”to achieve it. The following is an example::
26.jpg
The final output is shown below:  UNION() vs DISTINCT(UNION())
newtable1 = UNION('Table','Table (2)')      vs      newtable2 = DISTINCT(UNION('Table','Table (2)'))

v-yalanwu-msft_1-1619404533473.png

Best Regards,
Community Support Team_ Yalan Wu
If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.

HotChilli
Super User
Super User

It's not a bug.

"A table that contains all the rows from each of the two table expressions"

"Duplicate rows are retained"

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