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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])
please define "duplicate" and "identify". Does that include the first occurrence? If yes then you can do a table self join.