Format and syntax-check SQL in the browser
Without connecting to a database, select from six dialects to format or minify SQL and check basic issues with parentheses, quotes, and comments.
Open SQL formatting, compression, and syntax check toolConclusion: Fix structural errors one at a time and reparse in the target DB
Even if multiple errors are displayed, fixing the first unclosed quote or bracket may remove subsequent errors together. Start from the line, column, and surrounding excerpt, and return to the preceding opening token.
Before and after formatting, confirm that strings, quoted identifiers, comments, placeholders, operators, and statement delimiters have not changed.
The formatter does not automatically repair SQL or guarantee complete database-specific syntax validation or execution results.
Cause and decision criteria: Separate the display location from the root cause
If a Quote is not closed, subsequent Keywords may also be treated as a String and an Error may occur on the final line. The same applies to parentheses: distinguish an extra closing parenthesis from a missing closing parenthesis.
For keyword order, types, function arguments, and clause-specific errors not found by simple checks, consult the database error message and official grammar.
| Account to check | What to Verify | Actions after the decision |
|---|---|---|
| Parentheses | () depth and extra closing parentheses | Check corresponding position |
| String | Terminating '...' and escaping '' | Edit while preserving Literals |
| Identifier | "" · `` · [] | Select dialect |
| Comment | Termination of -- and /* */ | Check the import range of subsequent SQL |
Checklist to check after formatting
- Target database and version
- Quotes for strings and identifiers
- Preserve comments and hints
- Parentheses, statement delimiters, and placeholders
- Revalidate in the target database or CI
What can be checked with DevelopTools' SQL Formatter
SQL Formatter does not execute SQL. It tokenizes SQL and formats it according to clauses and parenthesis depth while protecting strings, quoted identifiers, and comments. You can select ANSI SQL, Oracle, PostgreSQL, MySQL/MariaDB, SQL Server, or SQLite; pasted input and .sql file loading are processed only in the Browser.
| Item | Support in the current Tool |
|---|---|
| processing | Checking simple syntax for formatting, single-line compression, parentheses, quotes, and comments |
| Formatting settings | 2 or 4 spaces or tabs; uppercase or lowercase keywords; leading or trailing commas; AND and OR line breaks |
| Retention settings | Comments, blank lines, and trailing newlines. Choose LF or CRLF for line endings |
| Dialect protection | PostgreSQL dollar quotes, Oracle alternative quotes, MySQL backticks, and SQL Server bracketed identifiers |
| Diagnostics | Unclosed parentheses, quotes, and comments; line, column, surrounding excerpt, statement count, parameter count, and maximum parenthesis depth |
| Unsupported | Database connections, SQL execution, and complete validation of schemas, types, permissions, execution plans, and all dialect syntax |
Consider formatting, basic syntax checks, and database execution separately
Formatting makes whitespace and line breaks between tokens easier to read. Basic syntax checks verify whether parentheses, strings, quoted identifiers, comments, and similar constructs are closed. Neither verifies the existence of tables or columns, data types, permissions, constraints, entire stored procedures, or execution plans.
For SQL used in production, review formatted differences, then pass it to the target database parser, test database, migration tool, CI linter, and similar tools. Do not treat a clean appearance as the same judgment as safe and correct execution.
DevelopTools does not send or execute SQL against a database. “No syntax errors” does not guarantee successful execution on the target database.
Common steps for safely formatting and checking SQL
- Duplicate the original SQL and replace Passwords, Tokens, customer information, connection destinations, and real data with test values.
- Select the target dialect from Oracle, PostgreSQL, MySQL/MariaDB, SQL Server, SQLite, and ANSI SQL.
- First run syntax checking, then check unclosed parentheses, quotes, comments, and the displayed line and column.
- Choose formatting settings one at a time and review the diff to ensure strings, comments, and placeholders have not changed.
- Save the formatted result under a different name, then validate it again with the target database's official parser, a test environment, migration tool, or CI.
- Before execution, check the JOIN conditions, WHERE conditions, transaction scope, number of update and deletion targets, and execution plan.
Formatting UPDATE or DELETE does not make them safe. Separately check the WHERE condition, Transaction, Backup, and permissions.
Notes for handling confidential information and large SQL
Pasting, file loading, formatting, minification, basic syntax checks, copying, and saving are completed in the browser. LocalStorage stores settings such as dialect, indentation, theme, font, and editor size, not the input SQL body or processing results.
SQL can contain Schema names, Table names, customer IDs, Emails, Access Tokens, endpoints, and operational Comments. Even with Browser-only processing, consider leaks through screen sharing, Clipboard history, Download destinations, and Browser Extensions; replace sensitive information with a Masking Tool before sharing.
For input over 500,000 characters, omit syntax highlighting. Because the processable size depends on available device and browser memory, split huge dumps by statement or migration.
Check dialects and lexical rules in official database documentation
SQL reserved words, identifier quotes, strings, comments, and statement delimiters differ by database. Do not determine executability from formatting results alone; check official documentation for the DB and Version in use.
Example: SQL that reports an error at the end because of a missing closing quote
This is an example of an unclosed String, such as SELECT * FROM users WHERE status = 'OPEN AND created_at >= CURRENT_DATE;.
Do not overwrite the original SQL directly; run syntax checking and formatting separately. Compare output with a string diff, and verify it in a test environment for the target DB before execution.
- Paste SQL or load one .sql file.
- Select the target database and run a syntax check first.
- Return not only to the error line but also to the start of the status literal, add a quote at the end of the correct value, and check again.
- Compare the formatted result with the original SQL and confirm that literals, identifiers, comments, and parameters are the same.
- Verify syntax and execution results with the target database parser or test environment.
Do not infer values and autocomplete them; identify the correct literal from the specification or parameter-binding source.
Frequently asked questions
- Is the entered SQL sent to a Database or server?
- It is not sent. SQL loading, formatting, minification, basic syntax checks, copying, and saving are processed in the browser; it does not connect to or execute against a Database.
- If syntax checking succeeds, can it be run in production as-is?
- Not guaranteed. This feature checks basic Token structures such as parentheses, quotation marks, and comments; confirm Schema, types, permissions, complete dialect Grammar, execution plans, and update targets in the target DB.