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Frequent Visitor

Changing source with a reduced CSV file

Hi dear community,


I work to set a reporting weekly refreshed. The problem is I made my reporting with a huge exctraction (30 columns, 50mb), and for performance reasons we decided to now use a little version of the extraction (around 20 columns). I removed all non -essential columns in my Power Query, but after changing the source to my new reduced CSV, Power BI keeps asking me for deleted colums, despite the fact i dont need them anymore. 

Is someone has a solution for my problem ? 


(Sorry for my very basic english)

Community Champion
Community Champion

Hello @LZNPM ,


It may be because there are some steps in Power query that reference these columns, so look into power query and see where is the error is coming from and remove the solumn names from the steps that has them.


If I answered your question, please mark my post as solution, Appreciate your Kudos 👍

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Thank you for your quick response. 
I made what you suggest until my Power Query step where I delete my non essentials columns. 
I suppose I maybe have to delete those columns upstream in my original CSV file ? But I expect my Power Query will dont run at all from the start then ?

Hello @LZNPM ,


Just look at the advanced editor to see the M code for the applied steps and search for the removed columns if they're still referenced.


If I answered your question, please mark my post as solution, Appreciate your Kudos 👍

Follow me on Linkedin

I get what you suggest ! But in the M code of the my deleting step I have to refer to my suppressed columns. 

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