SQL Formatter

01 Dialect Compatibility

02 Formatting Principles

• 📏
  Vertical Rhythm CTEs at the top, followed by the main SELECT. Each column on its own line to make Git diffs readable.
• ✨
  Keyword Casing Standardize on UPPERCASE for traditional readability or lowercase for modern dbt-style conventions.
• 🔍
  Operator Alignment Boolean AND/OR placed at the start of new lines for logical clarity and easier debugging.

03 Why You're Pasting a Query In Here

Most of the SQL you'll format isn't yours, it's an ORM dump, a 200-line analytics view someone shipped years ago, or an EXPLAIN that needs to fit on one screen.

• 🔍
  Code-reviewing a 200-line analytics query Half the comments on a SQL PR are about formatting. Run it through the formatter once and the discussion shifts to actual semantics, join correctness, NULL handling, window-function partitions.
• 🤖
  Inspecting ORM-generated SQL Hibernate, SQLAlchemy, and ActiveRecord all emit single-line SQL with verbose alias names. Formatting reveals the N+1 in your includes chain or the eager-load that fanned out into 12 joins.
• 📊
  Debugging EXPLAIN plans A formatted query lines up visually with the plan's join order, easier to see which subquery became the costly Seq Scan on a 50M-row table.
• 📚
  Normalizing query history for similarity pg_stat_statements already normalizes; for raw slow-log dumps, formatting first makes it easier to group "same query, different literals" by visual diff.
• 🧪
  Preparing snippets for docs & tickets A formatted query in a bug report saves the reviewer 30 seconds of mental parsing. Trivial, and the kind of trivial that compounds across a team.

04 Worked Examples

SELECT
  u.id,
  u.email,
  u.created_at,
  COUNT(o.id) AS order_count
FROM users u
LEFT JOIN orders o ON o.user_id = u.id
GROUP BY u.id, u.email, u.created_at;

SELECT
    u.id
  , u.email
  , u.created_at
  , COUNT(o.id) AS order_count
FROM users u
LEFT JOIN orders o ON o.user_id = u.id
GROUP BY u.id, u.email, u.created_at;

FROM orders o
INNER JOIN customers c ON c.id = o.customer_id
LEFT JOIN refunds r ON r.order_id = o.id AND r.status = 'completed'
LEFT JOIN payments p ON p.order_id = o.id AND p.captured_at IS NOT NULL

FROM       orders    o
INNER JOIN customers c  ON c.id        = o.customer_id
LEFT  JOIN refunds   r  ON r.order_id  = o.id
                      AND r.status     = 'completed'
LEFT  JOIN payments  p  ON p.order_id  = o.id
                      AND p.captured_at IS NOT NULL

WITH active_users AS (
  SELECT id, email FROM users WHERE deleted_at IS NULL
),
recent_orders AS (
  SELECT
    o.id,
    o.user_id,
    o.total
  FROM orders o
  WHERE o.created_at >= NOW() - INTERVAL '30 days'
),
summary AS (
  SELECT
    au.id,
    au.email,
    SUM(ro.total) AS spend_30d
  FROM active_users au
  LEFT JOIN recent_orders ro ON ro.user_id = au.id
  GROUP BY au.id, au.email
)
SELECT * FROM summary WHERE spend_30d > 100;

Postgres :  "user"           -- double quotes for identifiers
MySQL    :  `user`           -- backticks
Snowflake:  "USER"           -- double quotes; case-folds UPPER by default
SQL Server: [user]           -- square brackets (also "user")

05 Related Tools

Formatting is step one of any SQL workflow. These tools cover the steps that come next.