How to Format SQL in PostgreSQL: Styles, Tools, and Team Standards

The short version

Unformatted SQL — a 400-character single line from your logs, an ORM dump with random indentation — slows down everyone who reads it. Formatting is a solved problem: paste it into a formatter, pick a style, move on.

dbdiagramr's free SQL formatter formats PostgreSQL in your browser. Uppercase or lowercase keywords, 2 or 4 space indent, copy or download. Nothing is uploaded.

What "formatted" actually means

Take this real-world log line:

select u.email, count(p.id) as post_count from users u left join posts p on p.user_id = u.id where u.created_at > now() - interval '30 days' group by u.email order by post_count desc limit 20;

Formatted:

SELECT
  u.email,
  count(p.id) AS post_count
FROM
  users u
  LEFT JOIN posts p ON p.user_id = u.id
WHERE
  u.created_at > now() - interval '30 days'
GROUP BY
  u.email
ORDER BY
  post_count DESC
LIMIT
  20;

Same query. The second version shows the misplaced JOIN or wrong GROUP BY in seconds; the first hides it.

Uppercase vs lowercase keywords

There is no technical difference — Postgres parses both identically. It is purely culture:

• UPPERCASE — traditional DBA style, SQL Server and Oracle shops, certification materials. Keywords visually pop against table names.
• lowercase — modern analytics style (dbt, Postgres-first teams). Less shouting, easier to type.

Pick the one that matches your codebase and enforce it with a formatter, not a style doc nobody reads.

Where formatting pays off most

• Migration PRs — formatted DDL diffs review in minutes; single-line dumps review never.
• Log triage — paste the slow query from pg_stat_statements or your app logs and read it.
• Onboarding — new hires can read the schema migrations as documentation.
• Before diagramming — clean SQL is easier to sanity-check before you visualize it as an ER diagram.

FAQ

Does formatting change what my query does?
No. A formatter only changes whitespace and keyword casing. Same semantics, better manners.

Can I format SELECT queries or only DDL?
Both — SELECTs, CTEs, JOINs, migrations, anything valid PostgreSQL.

Is my SQL sent to a server?
Not with dbdiagramr's formatter — it runs entirely in your browser.