Advanced SQL Best Practices

Advanced SQL pays off when readable and measured.

How to Use This List

• Require EXPLAIN for new CTE/window/lateral queries.
• Store complex SQL in repo, not hidden ORM strings.

A - Clarity

• Name CTEs by business step. Not cte1.
• Comment invariant assumptions. Status values documented.
• Limit dynamic SQL to proven cases. Injection and plan risk.

B - Performance

• EXPLAIN ANALYZE before prod. Especially window and sort nodes.
• Index PARTITION BY and JOIN keys. Match window ORDER BY.
• Materialize expensive CTE once when reused. AS MATERIALIZED.

C - Safety

• Guard recursive CTE depth. Cycle detection.
• Test NULL partition rows. Window frames with sparse data.
• Version SQL with migrations. Reviewable diffs.

FAQs

Related

• Window Functions - analytics
• EXPLAIN Basics - plans

External Related Links

• Official PostgreSQL Documentation - Central hub for all manuals.
• Awesome Postgres - Curated collection of tools, libraries, extensions, and resources.
• Stack Overflow – PostgreSQL Tag - Q&A for practical PostgreSQL problems.
• Learn PostgreSQL (2nd Edition) - Luca Ferrari & Enrico Pirozzi.
• Just Use Postgres! - Denis Magda.

Stack versions: This page was written for PostgreSQL 18.4 (stable 18, maintenance 17), pgvector 0.8+, PgBouncer 1.x, Patroni 3.x, and PostGIS 3.5+.