After the archive post , I got a good question: what happens when an old row must change after its year has been written to Parquet? Rewriting a large immutable file for every correction or deletion would defeat much of the purpose of the archive. My first answer is to archive a fact only once the business considers it immutable. Historical sales shouldn’t change silently after reports are published. Personal data, however, follows a different lifecycle: a customer's name, email, phone numbe...