SQL Indenter and Formatter

What is SQL formatting and what is this tool for?

SQL (Structured Query Language) is the standard language for querying and manipulating relational databases such as PostgreSQL, MySQL, SQLite, SQL Server and Oracle. SQL queries written compactly — on a single line or without consistent indentation — are hard to read, review and debug, especially when they involve multiple JOINs, subqueries or long conditional clauses.

This tool performs a heuristic formatting of the SQL query directly in your browser. The available operations are:

• Format: puts each main clause (SELECT, FROM, WHERE, JOIN, GROUP BY, ORDER BY etc.) on a new line with configurable indentation; comma-separated items in the SELECT list are placed on their own lines; keywords are optionally standardized in uppercase.
• Minify: collapses the query into a single line with normalized spaces — useful for reducing the size of queries embedded in code or logs.
• Configurable indentation: choose between 2 spaces, 4 spaces or tab to match your team's standard.

The tool is useful for developers who need to inspect queries generated by ORMs, review migration SQL or document complex queries in a readable way.

Frequently Asked Questions (FAQ)

Does the tool support all SQL dialects?

This is a keyword-based heuristic formatting, not a full SQL parser. It recognizes the most common clauses (SELECT, FROM, WHERE, JOIN, GROUP BY, ORDER BY, HAVING, LIMIT, OFFSET, INSERT INTO, VALUES, UPDATE, SET, DELETE FROM, UNION and JOIN variants). Very unusual dialect-specific syntax or proprietary extensions may not be formatted ideally.

Are strings and comments preserved?

The tool makes a reasonable effort not to break literals between single quotes (e.g., 'value'). However, since it is not a full parser, strings that contain SQL keywords (e.g., 'select from') or comments (-- comment, /* block */) may not be 100% preserved in all cases. For queries with complex strings or comments, always check the result before using it.

Is the formatted query executable without modifications?

Generally yes — formatting does not change the semantics of the query, it only reorganizes whitespace and line breaks. However, since this is a heuristic formatting, it is always recommended to test the formatted query on your database before using it in production.

What is the difference between formatting and minifying?

Formatting expands the query with indentation and line breaks to make it easier for humans to read. Minifying does the opposite: it produces a single line with normalized spaces, ideal for use in code or comparing queries.

Can I use tab as indentation?

Yes. Select the Tab option in the indent selector before clicking Format. Choosing between spaces and tab is a team preference or project convention.