My Power BI Desktop is very slow

[msjules2023]

Hi all, 

When I do transformations in dataset in Power Query and I applied, Power Bi become slow to apply transformations. I need your help for this mistake.

Yours sincerely

[parry2k]

@msjules2023 ok, then you don't need to merge, you can load both tables independently and set the relationship between the tables on this common column. I assume this is one to many relationship.

[parry2k]

@msjules2023 not sure if that answered my previous question.

[msjules2023]

Hello @parry2k, your question was, "how you are merging when there are no common keys? " I mentioned that there common key was 'Numéro_dossier_conrevent' which is a string lets me know if you need others informations. My transformations in power query are very slow.

[parry2k]

@msjules2023 how you are merging when there are no common keys? 

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[parry2k]

@msjules2023 thanks for subscribing. Joining - so-called merging is an expensive transformation and can be very slow, although you don't require merging in most cases, it is hard to tell though. Why you are doing the merging?

[msjules2023]

Hi @parry2k, I'm doing merging to create relation between tables as it's in the original data base.

[msjules2023]

Thanks for your reply @parry2k 

My data source is MS Access data base, I'm designing a dataset for a report. Transformations = only joining tables of dataset. I subscribed to the channel @PowerBIHowTo

Yours sincerely 

[parry2k]

@msjules2023 what are your data source? What kind of transformation you are doing? What is the size of the data?Lot of it depends on many factors but let's start with these questions.

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If my solution proved useful, I'd be delighted to receive Kudos. When you put effort into asking a question, it's equally thoughtful to acknowledge and give Kudos to the individual who helped you solve the problem. It's a small gesture that shows appreciation and encouragement! ❤️

[msjules2023]

Helle @parry2k, I'll give kudos don't worry about. 

the message is : "The column 'Numéro_dossier_conrevent' of the table 'DossierPlainte/Contrevenant' contains a duplicate value '1917'. This is not allowed for columns that are used as the primary key of a table". The common key is 'Numéro_dossier_conrevent'. How should I do to solve this mistake ? Thanks