I have done, quite literally, thousands of database migrations in a telco context and we never - not one time - lost information. I don’t think there is any pa

I have done, quite literally, thousands of database migrations in a telco context and we never - not one time - lost information. I don’t think there is any particular problem, or solution. Applications get old, assumptions change, the world moves in. It’s true that our database design became inflexible over time and needed to be hoisted. But so too did our authentication layer (hand built - JaaS - JWT), the UI (AWT - Swing - Web 1.0 - Web 2.0), the deployment model (on prem - cloud - docker), even the API scheme (RMI - soap - rest - graphql). Any application that lives long enough is going to go through this sort of change. The only constant in all of the above was SQL.