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michaelshparber
Advocate V
Advocate V

Power Query Terrible Performance

‎08-31-2019 12:43 AM

I am working with 250K rows of data - nothing fancy

Everything is moving quick but when I do a couple of Merges - that's it!

About 50% of the time I spend on project is waiting for Power Query.

Even AFTER the Merge / Expand Step is finished - all sequential steps (even simple Add Column with if calculation ) - they take forever. Is is calculating all over again!!!

An I don't have any cartesian joins - only simple one-to-many merges.

A nightmare!

Once it passed the merge/expand - It shouldn't rerun all the next steps again.

How to do this? Any ideas?

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ImkeF
Community Champion
Community Champion
In response to Greg_Deckler

‎09-01-2019 06:01 AM

Hi @michaelshparber , 

Have you checked out the points from this list?: https://www.thebiccountant.com/speedperformance-aspects/ 

Imke Feldmann (The BIccountant)

If you liked my solution, please give it a thumbs up. And if I did answer your question, please mark this post as a solution. Thanks!

How to integrate M-code into your solution -- How to get your questions answered quickly -- How to provide sample data -- Check out more PBI- learning resources here -- Performance Tipps for M-queries

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Greg_Deckler
Community Champion
Community Champion

‎09-01-2019 05:02 AM

This sounds like something that @ImkeF might be able to help out on.



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ImkeF
Community Champion
Community Champion
In response to Greg_Deckler

‎09-01-2019 06:01 AM

Hi @michaelshparber , 

Have you checked out the points from this list?: https://www.thebiccountant.com/speedperformance-aspects/ 

Imke Feldmann (The BIccountant)

If you liked my solution, please give it a thumbs up. And if I did answer your question, please mark this post as a solution. Thanks!

How to integrate M-code into your solution -- How to get your questions answered quickly -- How to provide sample data -- Check out more PBI- learning resources here -- Performance Tipps for M-queries

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michaelshparber
Advocate V
Advocate V
In response to ImkeF

‎09-03-2019 01:04 PM

@ImkeF 

Great, thanks, I already see some things that I do, like Grouping...

I'll definetely check it out, thanks!

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