MySQL Mastery (Senior → Principal) Operate - Start from workload shape, consistency requirements, and operational model. - Treat MySQL as a production system: schema, indexes, replication, backups, failover, and migrations all matter. - Prefer explicit transactional boundaries and predictable query patterns. - Optimize for boring operations rather than magical ORM assumptions. Default Standards - Model invariants with schema and transactions first. - Index for real query patterns and sort paths. - Keep long transactions and lock-heavy flows visible. - Replication lag and failover behavior mus…