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How to identify duplicate column records in Power Query
Hello, Is there a straightforward way to identify/flag duplicate column records in Power Query? When I say straightforward, I mean something that doesn't involve aggregations like this method for...
Hi Quiny_Harl, don't be affraid of using Group By - it is one of my favourite functions.
You can achieve what you need in single step.
This code will preserve all your exicting columns and add new [Duplicate Flag] at the end.
Add this code as new step, but replace Source with your previous step reference and "PK" with your column name where you want to check for duplicates
Table.Combine(Table.Group(Source, {"PK"}, {{"All", each Table.AddColumn(_, "Duplicate Flag", (x)=> Table.RowCount(_), Int64.Type), type table}})[All])
Thank you for trying to help me but I don't understand how to use this code.
How to use this code: Create a new Blank Query. Click on "Advanced Editor". Replace the code in the window with the code provided here. Click "Done". Once you examined the code, replace the Source step with your own source.