SQL Formatter

Welcome to the SQL Formatter, a powerful online tool that transforms messy, hard-to-read SQL queries into clean, properly indented code. Whether you are a developer, database administrator, or data analyst, this formatter helps you maintain consistent code style and improve readability across your SQL projects.

Why Format SQL Queries?

SQL formatting is essential for maintaining clean, maintainable database code. Here's why it matters:

Key Features

Multiple SQL Dialect Support

This formatter supports three popular SQL dialects:

• Standard SQL: The ANSI SQL standard, compatible with most database systems
• MySQL: Includes MySQL-specific keywords like AUTO_INCREMENT, ENGINE, SHOW, and more
• PostgreSQL: Supports PostgreSQL-specific features like RETURNING, SERIAL, JSONB, and ON CONFLICT

Customizable Formatting Options

Tailor the output to match your coding standards:

• Indentation: Choose between 2 spaces, 4 spaces, or tabs
• Keyword Casing: Convert keywords to UPPERCASE or keep them lowercase
• Comment Preservation: Keep inline comments (--) and block comments (/* */) intact

Real-Time Live Preview

See your formatted SQL instantly as you type or paste. No need to click buttons - the output updates automatically with every keystroke, giving you immediate feedback on how your formatting options affect the result.

Privacy-Focused Processing

All SQL formatting happens directly in your browser using JavaScript. Your queries are never sent to any server, ensuring complete privacy and security. This is especially important when working with queries that contain sensitive table names, column names, or data values.

How to Use the SQL Formatter

1. Paste your SQL: Enter your messy SQL query in the input panel on the left. You can paste directly from your code editor, database client, or any source.
2. Select your dialect: Choose Standard SQL, MySQL, or PostgreSQL from the dropdown to ensure dialect-specific keywords are handled correctly.
3. Configure options: Adjust indentation size, keyword casing, and comment handling according to your preferences.
4. View the result: The formatted SQL appears instantly in the output panel with syntax highlighting.
5. Copy or download: Use the Copy button to copy the result to your clipboard, or download it as a .sql file.

SQL Formatting Best Practices

Consistent Keyword Casing

Using uppercase for SQL keywords (SELECT, FROM, WHERE) and lowercase for table and column names (users, email) is a widely adopted convention that improves readability.

Logical Line Breaks

Each major clause should start on a new line. This makes it easy to scan the query structure and identify WHERE conditions, JOIN clauses, and other important elements.

Proper Indentation

Indent subordinate clauses and conditions to show their relationship to parent clauses. This hierarchical structure makes complex queries much easier to understand.

Comment Your Complex Logic

Add comments to explain non-obvious logic, business rules, or performance optimizations. Well-commented SQL is invaluable for future maintenance.

Supported SQL Statements

This formatter handles all common SQL statement types:

• SELECT queries: Including complex JOINs, subqueries, CTEs (WITH clauses), and window functions
• INSERT statements: Single and multi-row inserts, INSERT...SELECT, and UPSERT operations
• UPDATE statements: Simple updates and complex updates with JOINs or subqueries
• DELETE statements: Including DELETE with JOINs and subquery conditions
• DDL statements: CREATE TABLE, ALTER TABLE, DROP, CREATE INDEX, and more
• Transaction control: BEGIN, COMMIT, ROLLBACK, SAVEPOINT

Tips for Best Results

Handle Large Queries

For very large queries, the formatter processes efficiently in your browser. However, extremely complex queries with thousands of lines may take a moment to format.

Preserve String Contents

The formatter correctly preserves the contents of string literals (single quotes), identifiers (double quotes or backticks), and comments without modifying them.

Check Edge Cases

While the formatter handles most SQL syntax correctly, unusual or non-standard syntax might not format perfectly. Always review the output before using it in production.

Frequently Asked Questions

What is SQL formatting and why is it important?

SQL formatting is the process of restructuring SQL queries with proper indentation, line breaks, and consistent keyword casing to make them more readable. Well-formatted SQL is easier to understand, debug, and maintain. It helps teams collaborate more effectively and reduces the likelihood of errors when modifying complex queries.

Does this SQL formatter support different database dialects?

Yes, this SQL formatter supports multiple database dialects including Standard SQL, MySQL, and PostgreSQL. Each dialect has its own specific keywords and syntax that the formatter recognizes and handles appropriately. You can select your preferred dialect from the dropdown menu before formatting.

Is my SQL query data safe when using this formatter?

Absolutely. All SQL formatting happens directly in your browser using JavaScript. Your SQL queries are never sent to our servers or stored anywhere. This client-side processing ensures complete privacy and security for your database queries, even if they contain sensitive table names or data.

Can I customize the formatting options?

Yes, you can customize several formatting options including: indentation size (2 spaces, 4 spaces, or tabs), keyword casing (uppercase or lowercase), and whether to preserve inline comments. These options allow you to match your team's coding standards or personal preferences.

How does the live preview feature work?

The live preview feature formats your SQL query in real-time as you type or paste it. You can see the formatted result instantly without clicking any buttons. This immediate feedback helps you understand how your formatting options affect the output before copying or downloading the result.

Additional Resources

• SQL - Wikipedia
• PostgreSQL SQL Syntax Documentation
• MySQL SQL Statements Reference