Found the answer to the MySQL code. The search results I was finding related to content that was unintentionally duplicated and how to prevent it, but with a search on cloning, I found an answer that I was then able to manipulate.
INSERT INTO table (col1, col2, col3)
SELECT col1, col2, col3 FROM table
WHERE id = 1
It works a treat in Sequel Pro, but I can't figure out how to trigger the code to run. So, if you could advise on that, that'd be great.