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Anonymous
Not applicable

Merge issue

Dear Power BI community,

 

 

I tried to merge two files based on same customer ID (some customer ID doesn't have matches) using left outer join but it turns out that when I perform a verification after the match, the total order quantity before and after is different. Could anyone tell me what and why is this happening? Thanks

 

Merge issue.PNG

 

1 ACCEPTED SOLUTION
AnkitKukreja
Super User
Super User

Hi
This could be due to duplicates in your left or right table.
Left is easy to understand, but in right for example if you've duplicate Cust ID then those are also getting merged into your existing data which is increasing your count.

 

My advice, try count rows under transformin Query editor and remove duplicates and then try the same step, it would help you identify the issue.

 

 

Thanks,
Ankit Kukreja
www.linkedin.com/in/ankit-kukreja1904

For Power BI trainings or support dm or reach out to me on LinkedIn.
If my response has successfully addressed your question or concern, I kindly request that you mark this post as resolved. Additionally, if you found my assistance helpful, a thumbs-up would be greatly appreciated.

Thanks,
Ankit Kukreja
www.linkedin.com/in/ankit-kukreja1904

View solution in original post

2 REPLIES 2
AnkitKukreja
Super User
Super User

Hi
This could be due to duplicates in your left or right table.
Left is easy to understand, but in right for example if you've duplicate Cust ID then those are also getting merged into your existing data which is increasing your count.

 

My advice, try count rows under transformin Query editor and remove duplicates and then try the same step, it would help you identify the issue.

 

 

Thanks,
Ankit Kukreja
www.linkedin.com/in/ankit-kukreja1904

For Power BI trainings or support dm or reach out to me on LinkedIn.
If my response has successfully addressed your question or concern, I kindly request that you mark this post as resolved. Additionally, if you found my assistance helpful, a thumbs-up would be greatly appreciated.

Thanks,
Ankit Kukreja
www.linkedin.com/in/ankit-kukreja1904
MattAllington
Community Champion
Community Champion

Most likely the table on the left contains duplicates in the join column. 



* Matt is an 8 times Microsoft MVP (Power BI) and author of the Power BI Book Supercharge Power BI.
I will not give you bad advice, even if you unknowingly ask for it.

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