SQL is one of the few languages where formatting is genuinely optional — the engine doesn't care about whitespace, indentation, or casing. But your teammates do. And so does future-you.
The Core Rules
1. Uppercase keywords
Most style guides recommend uppercase SQL keywords and lowercase table/column names. It creates visual hierarchy:
``sql
SELECT id, name, email
FROM users
WHERE is_active = true
ORDER BY name ASC;
`
vs. the unformatted version:
<code>sql
<p>select id,name,email from users where is_active=true order by name asc;</p>
</code>
2. One clause per line
Each major clause starts on a new line. Conditions are indented:
<code>sql
<p>SELECT</p>
<p>u.id,</p>
<p>u.name,</p>
<p>COUNT(o.id) AS order_count</p>
<p>FROM users u</p>
<p>LEFT JOIN orders o</p>
<p>ON o.user_id = u.id</p>
<p>WHERE u.is_active = true</p>
<p>AND u.created_at > '2026-01-01'</p>
<p>GROUP BY u.id, u.name</p>
<p>ORDER BY order_count DESC</p>
<p>LIMIT 100;</p>
</code>
3. Indent subqueries
<code>sql
<p>SELECT *</p>
<p>FROM (</p>
<p>SELECT user_id, SUM(amount) AS total</p>
<p>FROM orders</p>
<p>WHERE status = 'completed'</p>
<p>GROUP BY user_id</p>
<p>) AS spending</p>
<p>WHERE spending.total > 1000;</p>
</code>
4. Use CTEs for complex logic
Common Table Expressions make multi-step queries readable:
<code>sql
<p>WITH active_users AS (</p>
<p>SELECT id, name</p>
<p>FROM users</p>
<p>WHERE is_active = true</p>
<p>),</p>
<p>high_spenders AS (</p>
<p>SELECT user_id, SUM(amount) AS total</p>
<p>FROM orders</p>
<p>GROUP BY user_id</p>
<p>HAVING SUM(amount) > 1000</p>
<p>)</p>
<p>SELECT au.name, hs.total</p>
<p>FROM active_users au</p>
<p>JOIN high_spenders hs ON hs.user_id = au.id</p>
<p>ORDER BY hs.total DESC;</p>
</code>`
Formatting Reference
| Element | Convention |
|---|---|
| SQL keywords | UPPERCASE |
| Table/column names | lowercase_snake_case |
| Aliases | Explicit AS keyword |
| Indentation | 4 spaces |
| Max line length | ~100 characters |
| Semicolons | Always close statements |
Why This Matters in Code Review
Badly formatted SQL creates two problems during review:
- The reviewer can't spot logic errors because they're fighting the formatting
- The author can't catch their own bugs because nesting obscures the query structure
With consistent formatting, a five-level JOIN query becomes scannable. Without it, you're debugging character-by-character.
Format Without Thinking About It
The SnappyTools SQL Formatter & Beautifier formats any SQL query in one paste. It handles indentation, keyword casing, and clause alignment. Takes 5 seconds and saves everyone who reads the code 5 minutes.
Runs in-browser, no upload, no account.
Does your team have a SQL style guide? Or does formatting vary by developer?