postgres
Postgres 19 adds SQL/PGQ graph queries over the tables you already have, an atomic ON CONFLICT DO SELECT upsert, and REPACK CONCURRENTLY that returns disk space without locking the table. Here is what each one replaces, with working SQL and the limits the release notes do not shout about.
postgresql
UUIDv7 arrives in PostgreSQL 18 as a built-in uuidv7() function. See what it changes in practice: friendlier indexes than UUIDv4, simpler Rails migrations, a schema example, and the security caveat that time-ordered does not mean secret.
postgres
PostgreSQL lock timeouts strike during long migrations and complex transactions. How lock_timeout and statement_timeout actually work, quick fixes at the database role level, managing timeouts in Rails migrations, and global protection with StrongMigrations.
PostgreSQL database size checks in a few simple SQL queries: list all databases with pg_database and pg_size_pretty, then break down the biggest tables in a schema, indexes included. Spot what eats disk space before it slows backups and raises infrastructure costs.
Slow SQL queries in Rails can be caught in development, before they become production fires. Using ActiveSupport::Notifications and the sql.active_record event, you build a small performance guard that logs every query above a time threshold straight to your console.
Idle PostgreSQL connections eat memory and can hit the max_connections limit, blocking your app. How to find old sessions in pg_stat_activity, close them safely with pg_terminate_backend, and automate the cleanup so hanging connections never pile up again.