Add a Key column to a Collection

[SoftDevBen]

I want to add a generated unique key column to a collection, using integers in an ascending order.

I had asked this question before, and got an excellent and workable answer from @RandyHayes , but can't find it under my previous account,  BenDonahue, nor anywhere else online. I remember that Last(FirstN()) was used, but haven't been able to figure out how, exactly.

Thank you for your assistance.

[RandyHayes · Accepted solution]

@SoftDevBen 

Was it this post?

Doesn't seem like it has what you are thinking of, but that was the closest one I could find from you.

If you are trying to add a index column to your collection, then you can use this formula:

With({_items: yourCollection},
    ClearCollect(yourCollection,
        ForAll(Sequence(_items),
            Patch(Last(FirstN(items)), {_index: Value})
        )
    )
)
     

I hope this is helpful for you.

[SoftDevBen]

THERE it is!

Sequence!!!

Thank you, yet again, @RandyHayes