How is MySQL syntax different from PostgreSQL?

MySQL uses backticks for identifiers (`column`); PostgreSQL uses double-quotes ("column"). MySQL has ON DUPLICATE KEY UPDATE for upserts; PostgreSQL has ON CONFLICT. MySQL has LIMIT … OFFSET on one line; PostgreSQL puts them on separate lines. Always pick the dialect matching your database.

Does this work for MariaDB too?

Yes. MariaDB shares ~99% of its syntax with MySQL — backtick identifiers, the same data types, and most of the same reserved words. The MySQL preset handles MariaDB queries correctly.

Will formatting affect MySQL performance?

No. The MySQL optimiser sees the same logical query regardless of formatting. Performance comes from indexes, query plans, and storage engine choice — not whitespace or keyword case.

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MySQL Formatter

Format

Format MySQL-flavored SQL with MySQL-specific syntax support.

Input

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Output

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✨ AI Code Explanation

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What Is a MySQL Formatter?

A MySQL formatter rewrites MySQL (and MariaDB) queries with consistent indentation, keyword casing, and clause alignment. It understands MySQL-specific syntax including backtick identifiers (`column`), LIMIT … OFFSET, ON DUPLICATE KEY UPDATE, STRAIGHT_JOIN, and the RAND()/NOW() function family. Formatted MySQL is dramatically easier to read, debug, and review.

MySQL Formatter Online — What This Tool Does

This free MySQL formatter beautifies MySQL queries entirely in your browser using the sql-formatter library with the MySQL dialect preset. Supports keyword casing (UPPER/lower/preserve), 2/4/tab indent, and comment stripping. Runs entirely locally — your queries never leave your machine.

How to Format MySQL Queries

Paste your MySQL or MariaDB query into the Input pane, or click Upload to load a .sql file.
Confirm the dialect is MySQL (selected by default for this route).
Pick keyword case — ABC (uppercase, standard), abc (lowercase), or – (preserve original).
Pick indent: 2 spaces, 4 spaces, or tab.
Optional: enable No comments to strip -- and /* */ comments first.
Click Format. The formatted query appears in the output pane.
Click Copy or Download.

MySQL-Specific Syntax Handled

Backtick identifiers — `order` for reserved words used as column names.
LIMIT … OFFSET — paginated result clauses.
ON DUPLICATE KEY UPDATE — upsert syntax unique to MySQL.
INSERT IGNORE — silently skip duplicate-key conflicts.
STRAIGHT_JOIN, FORCE INDEX — optimiser hints specific to MySQL.
Storage engine hints — ENGINE=InnoDB in DDL.

MySQL vs PostgreSQL Formatting Differences

MySQL uses backticks for identifiers; PostgreSQL uses double-quotes. MySQL has LIMIT … OFFSET and ON DUPLICATE KEY UPDATE; PostgreSQL has LIMIT + OFFSET on separate lines and ON CONFLICT. Always pick the matching dialect — formatting MySQL with the PostgreSQL preset can mangle backtick identifiers and unrecognised reserved words.

Common Use Cases

Code review — format auto-generated MySQL from ORMs (Doctrine, Eloquent, Sequelize) for human review.
Stored procedure cleanup — beautify legacy stored procs before refactoring.
Migration scripts — format migrations before merging to keep diffs clean.
Onboarding — format unfamiliar queries for easier learning.

Tips & Tricks

Uppercase keywords for the SQL standard look — most MySQL conventions use SELECT, FROM, WHERE in UPPER.
Test in MySQL Workbench — paste the formatted output to verify execution.
Strip comments before sharing in tickets — internal comments may contain sensitive context.
Use the SQL Minifier when embedding queries in code.

Related Tools

SQL Formatter — generic ANSI SQL formatting.
PostgreSQL Formatter — PostgreSQL-specific dialect.
SQL Beautifier — alternate naming for the same operation.
SQL Minifier — opposite operation, compress SQL.
JSON to SQL — generate MySQL INSERTs from JSON.

Is My SQL Sent to a Server?

No. MySQL formatting runs entirely in your browser using the sql-formatter library. Your queries — including any production credentials, table names, or business logic — never leave your machine.