How do you keep your MySQL skills current, and how do you decide whether a new feature or version is worth adopting?

Answer in two halves — how you learn, and how you filter.

How you learn: the official MySQL release notes and worklogs, the Percona and PlanetScale engineering blogs, and — most persuasively — a local instance you deliberately break. Reading about EXPLAIN ANALYZE is not the same as running it against a badly written query and watching the row estimates drift.

How you filter: a new version or feature has to clear three bars before you would put it in production:

• Does it solve a problem we actually have, measured, rather than one we might have?
• Is it out of the earliest releases and running somewhere at comparable scale?
• Can we roll back if it disappoints, and have we tested that rollback?

Note: Naming one feature you chose NOT to adopt, and why, is more convincing than listing ten you like.