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Anonymous
Not applicable

PowerQuery editor at each step reloading source CSV file (becoming SLOWWWW...)

I'm using the PQ editor from Excel, loading a relatively small CSV file (3.6 MB), with a moderate number of rows (18,000), which, in the PQ editor, I then group into a much smaller table with under 100 rows and 7 columns.

 

However, each time I add an even simple step such as changing the data type from Whole number to Text, PQ seems to reload the source data all over again: I can see the lower right corner showing a progress message like "xxx MB from [file name.CSV]" with the xxx number going up, until ending with a mesage saying "PREVIEW DOWNLOADED AT 10:35 AM".  Why is PQ doing this?  I've tried fiddling with the Query Options with no luck.

  

I've already tried "Column profiling based on to 1000 rows", BTW. Does nothing, still reloads the file with each new step.

2 ACCEPTED SOLUTIONS
mahoneypat
Microsoft Employee
Microsoft Employee

In File/Options and Settings/Options, under Data Load (Global and/or Local File) uncheck the "Allow background refresh ..." option.

 

Pat

 





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Anonymous
Not applicable

This did it! Thanks so much

View solution in original post

4 REPLIES 4
KT_Bsmart2gethe
Impactful Individual
Impactful Individual

Hi  @Anonymous ,

 

Where did you saved the source file?

 

Regards

KT

Anonymous
Not applicable

In a Google Drive shared folder

mahoneypat
Microsoft Employee
Microsoft Employee

In File/Options and Settings/Options, under Data Load (Global and/or Local File) uncheck the "Allow background refresh ..." option.

 

Pat

 





Did I answer your question? Mark my post as a solution! Kudos are also appreciated!

To learn more about Power BI, follow me on Twitter or subscribe on YouTube.


@mahoneypa HoosierBI on YouTube


Anonymous
Not applicable

This did it! Thanks so much

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