MySQL vs PostgreSQL: Key Syntax Differences
The MySQL vs PostgreSQL syntax differences that break migrations: auto-increment, quoting, string concat, upserts, and NULL functions — with side-by-side SQL.
Read postMySQL SQL Formatter & Validator
Paste MySQL SQL to format it consistently and validate it against MySQL's actual grammar, including backtick-quoted identifiers and MySQL-only statements a generic formatter would misread.
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INPUT286 chars
select u.id, u.name, count(o.id) as order_count, sum(o.total) as lifetime_value from users u left join orders o on o.user_id = u.id where u.created_at >= '2026-01-01' and u.status in ('active', 'trial') group by u.id, u.name having count(o.id) > 0 order by lifetime_value desc limit 25;FORMATTED7 lines
INSERT INTO
`orders` (`id`, `customer_id`, `total`)
VALUES
(1001, 42, 89.99)
ON DUPLICATE KEY UPDATE
total = values(`total`),
updated_at = now();ANALYSISno issues
Syntax looks valid — no misspelled keywords or anti-patterns found.
MySQL-specific syntax sqlfmt understands
Backtick-quoted identifiers
MySQL uses backticks, not double quotes, to quote identifiers that clash with reserved words or contain spaces. A formatter that only understands ANSI double-quoted identifiers will treat backtick-quoted names as a syntax error.
SELECT `order`, `group` FROM `user` WHERE `order`.status = 'active';ON DUPLICATE KEY UPDATE
MySQL's upsert syntax appends ON DUPLICATE KEY UPDATE to an INSERT, updating the row in place if it collides with a unique key instead of erroring. It has no equivalent clause in standard SQL, so generic validators often stumble on it.
INSERT INTO counters (id, hits) VALUES (1, 1) ON DUPLICATE KEY UPDATE hits = hits + What the parser actually knows
Beyond standard SQL, sqlfmt's MySQL dictionary recognizes these as valid syntax:
- Statement starters
- REPLACE, LOAD, LOCK, UNLOCK, ANALYZE, OPTIMIZE
MySQL guides
Single vs Double Quotes in SQL: When to Use Each
Single quotes are for string values, double quotes are for identifiers — but MySQL, SQL Server, and BigQuery bend the rule. The full guide, with examples.
Read postSQL Reserved Words: What Silently Breaks Your Query
Reserved words like ORDER, GROUP, and USER silently break SQL queries used as column names. See which words are reserved per dialect and how to quote them.
Read postFAQs
Does sqlfmt format backtick-quoted identifiers correctly?
Yes. Backticks are parsed as MySQL identifier quoting, not as a syntax error, and preserved exactly as written in the formatted output.
Can I format MySQL-specific statements like LOAD DATA or REPLACE?
Yes — sqlfmt's MySQL dictionary includes REPLACE, LOAD, LOCK/UNLOCK TABLES, ANALYZE, and OPTIMIZE as valid statement starters, so they're recognized rather than flagged.
Is MySQL formatting free?
Yes — all five dialects, including MySQL, are free with no account required. Pro adds unlimited daily analyses, live formatting as you type, saved snippets, and REST API access.
Does my SQL get uploaded anywhere?
No. Formatting and validation run entirely in your browser; your SQL is only sent anywhere if you choose to save a snippet or create a share link while signed in.