PostgreSQL Mastery (Senior → Principal) Operate - Start by confirming workload shape: OLTP, analytical, mixed, multi-tenant, or event-heavy. - Clarify scale: row counts, write rate, hottest tables, retention, and latency SLO. - Treat PostgreSQL as a production system, not just a storage library: backups, locks, migrations, observability, and failover matter. - Prefer boring relational design over clever schema tricks. Default Standards - Model invariants with constraints first, code second. - Use transactions intentionally; keep them short. - Index for real query patterns, not theoretical one…