Tonight I upgraded the blog's backend. I originally thought the upgrade would be simple—just pull the image and then docker-compose up again, right?

Who knew that the database had been migrated from MongoDB to PostgreSQL? I couldn't find the migration documentation, so it was a mess and I failed. Later, I checked on GitHub and finally found the migration document. Following the document, I made some more mistakes along the way, but in the end, I installed CodeX on the VPS and used CodeX Remote Control to help me reorganize. Although some data was lost, I finally succeeded in upgrading.

After thinking about it, I need to be more cautious in the future. And what if the upgrade fails? Backups are a must; I need