Searching Google Sheet and Creating new Row if Record Not Found

I’m trying to search for or “filter” on a record in a Google Sheet. If that record does not exist, I would like to create a new Row where I’ll set values. If it exists, I would update specific columns in the row. It seems like you would do this with a “Router” but I don’t see any logical operators in the Router. How would you approach this?
Thanks for any help!

Hi Craig,
You should first search your Google Sheet for the specific key using an array aggregator that captures the column holding the key and its corresponding row number. After checking if the record with the unique ID exists via a router setup (using conditions), you can either update the existing row or create a new one based on whether the key is found.
Cheers,
Harsh