Power query formula needed

[lherna3]

 I need to compare multiple rows for matches in the same column and add a suffix when the rows have the same information. 

In the figure below you can find my column "Nom", it can be repeated several times and I woudl like to add suffix "A", "B", "C", etc. for the same "Nom" number and leave it as it is if it doesn't repeat. 

I appreciate your help, I've been trying for several hours 

[Ahmedx]

Based on your description, I created data to reproduce your scenario. The pbix file is attached in the end.

[Ahmedx]

I changed the M code, try again

[Ahmedx · Accepted solution]

and this is if you need the alphabet sequence A, B, C...

[lherna3]

Thank you very much! That is exactly what I was looking for. 

[Ahmedx]

If this post helps, then please consider Accepting it as the solution to help the other members find it more quickly

[Ashish_Mathur]

Hi,

Why does the third entry of each id nt have a - A?