You'd have a database table where its entire contents explain what's been done to the database schema and the data migrations. And then you make inserting a ro

You'd have a database table where its entire contents explain what's been done to the database schema and the data migrations. And then you make inserting a row named '3-add_customers_table' as part of the transaction for the migration. If this row already exists, the insert will fail, aborting the entire transaction. Or something like that...