How to generate unique values for the Primary Column

CLH

I'm new to Smartsheet and experimenting, and I hope this question makes sense — tell me if I should be trying a different plan

I have a sheet and I have what I think of in database terms as a composite key, that is what makes each row unique is the Member Number and the Event. I know that I can't define a primary column as two columns, so was going to just set up an Autocounter in the Primary Counter. But that's not permitted either. So now I'm looking for a way to set up a formula that would use something like
=IFERROR((MAX([Primary Column]) + 1),1)

but that's #UNPARSEABLE.

Do I have the wrong syntax for the formula to calculate the next highest#?
Is this an illegal formula because it's iterative?
Is it illegal to put a formula into the Primary column?
Maybe something else?

Chuck

Sam_Harwart

https://community.smartsheet.com/discussion/141371/how-to-generate-unique-values-for-the-primary-column

@CLH, You're on the right track.

You can't put an auto-number in the Primary column but you CAN put a formula.

As Andre described, you'll want to set up an auto-number column. Let's call it [AutoNumber]. Then you've already got your [Event] Column.

For the Primary column, put a formula in there like:
=[AutoNumber]row + " - " + [Event]@row

Once you add that to a single row, right-click on it and make it a column formula.

That should give you what you're looking for, but feel free to reply here if you have any questions or want to adjust it!