[semiquaver]

What has worked in my experience:

- decouple migration execution from code deployment. Require that all migrations are in totally separate PRs can be run well-in-advance of the code that depends on the db change being run

- maintain a stateful migration execution system using an online schema change system supervised by DBAs

- PRs adding migrations still need to be merged and deployed, but can only do so after the actual migration has run.

[tianzhou]

+1. We have been working on a schema migration tool called Bytebase for 3+ years. And we follow the similar principles.