Best practices · Stacks and tools
PostgreSQL Best Practices
Opens with creditsA practical guide to PostgreSQL best practices for application developers. It covers schema design and data types, constraints, indexing with EXPLAIN, query patterns that avoid N+1 problems, migrations that do not lock production, connection pooling, transactions and isolation, backups you have actually restored, and roles with least privilege.
Written by Tauseef Fayyaz7 chapters, 32 practicesAbout 21 min28 quiz questionsReviewed 12 October 2026What you will learn
7 chapters · about 21 min
1Schema design and data typesThe choices that are expensive to change once data is in the table: column types, primary keys and when to reach for JSON.5 practices · 4 min
2Constraints that protect your dataLet the database reject bad data so every app, script and admin console that writes to it follows the same rules.4 practices · 2 min
- Indexing and EXPLAINHow to choose indexes from real queries and how to read a query plan to see whether they are used.4 practices · 3 minOpens with credits
- Writing queries that scaleQuery patterns from application code that keep load on the database predictable as data and traffic grow.5 practices · 3 minOpens with credits
- Migrations without downtimeHow to change a busy production schema without long locks, using the tools PostgreSQL gives you for exactly this.5 practices · 3 minOpens with credits
- Connections and transactionsHow to keep connection counts sane and transactions short and correct, especially from serverless and multi-instance apps.4 practices · 3 minOpens with credits
- Backups, upgrades and securityRunning Postgres safely: backups you can restore, supported versions, and roles that limit what a leaked password can do.5 practices · 3 minOpens with credits
About this guide
PostgreSQL best practices matter most at the moment your app stops being small. A schema with the wrong types, a missing index on a foreign key or a migration that locks a busy table works fine with a thousand rows and falls over at ten million. Postgres gives you strong tools for all of this, but it will not stop you from skipping them.
This guide starts with the decisions that are hardest to change later: choosing data types and identifiers, and letting constraints protect your data. It then moves through indexing and reading EXPLAIN output, writing queries that do not hammer the database, changing the schema without downtime, pooling connections and handling transactions correctly, and finally backups, upgrades and database security.
Everything here was checked against the PostgreSQL 18 documentation (current minor release 18.6), including features new in 18 such as uuidv7(), virtual generated columns and NOT NULL constraints that can be added as NOT VALID. Each practice says what to do, why, and how to check it, usually with SQL you can run.
Common questions
What is the latest version of PostgreSQL?
As of October 2026 the latest stable major version is PostgreSQL 18, with 18.6 as the current minor release. PostgreSQL 19 is in beta. Check the versioning page on postgresql.org for the current table.
Should I use UUID or bigint for primary keys in PostgreSQL?
A bigint identity column is smaller and fast to index, which makes it a good default. Use UUIDs when IDs are generated outside the database or must be hard to guess. If you use UUIDs, prefer time-ordered UUIDv7, which PostgreSQL 18 generates with uuidv7().
How do I add an index in PostgreSQL without locking the table?
Use CREATE INDEX CONCURRENTLY. Writes continue during the build, but it takes longer and cannot run inside a transaction block. If it fails, drop the leftover invalid index and try again.
Why is my PostgreSQL query slow?
Run EXPLAIN ANALYZE on it and compare estimated rows to actual rows. Common causes are a missing index, stale statistics, a sequential scan on a large table or an N+1 pattern in the application. Fix the cause the plan shows instead of guessing.
Do I need PgBouncer with PostgreSQL?
You need some pooling. A single long-running app can use its driver's built-in pool. Serverless functions or many app instances usually need an external pooler such as PgBouncer or your provider's pooler, because each Postgres connection is a separate process.
What is the difference between timestamp and timestamptz in PostgreSQL?
timestamp stores a date and time with no time zone, so the same value can mean different instants. timestamptz stores an absolute point in time and converts it to the session time zone on display. Use timestamptz for events and audit times.
Sources (8)
Checked against these, last on 12 October 2026.
- Versioning Policy, PostgreSQLwww.postgresql.org/support/versioning/
- Release 18, PostgreSQL docswww.postgresql.org/docs/18/release-18.html
- Using EXPLAIN, PostgreSQL docswww.postgresql.org/docs/current/using-explain.html
- CREATE INDEX, PostgreSQL docswww.postgresql.org/docs/current/sql-createindex.html
- ALTER TABLE, PostgreSQL docswww.postgresql.org/docs/current/sql-altertable.html
- Transaction Isolation, PostgreSQL docswww.postgresql.org/docs/current/transaction-iso.html
- PgBouncer features, PgBouncerwww.pgbouncer.org/features.html
- Backup and Restore, PostgreSQL docswww.postgresql.org/docs/current/backup.html
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