
The Database Changed Before the Deployment Finished
A schema migration and an application deployment do not happen at one instant. Zero-downtime changes work when old code, new code, and the database are allowed to coexist for a while.
9 min read

A schema migration and an application deployment do not happen at one instant. Zero-downtime changes work when old code, new code, and the database are allowed to coexist for a while.

SQL becomes much easier when you stop thinking in tables and start thinking in facts that must remain true. A checkout model shows where keys, JOINs, transactions, and indexes actually earn their place.

"Add a database" used to mean provisioning a server, managing connections, and running migrations by hand. Serverless quietly rewrote that whole sentence. Here's what a React developer actually needs to know about picking and using a database in 2026.