SQL Validator & Syntax Checker
Validate your SQL queries online. Check syntax, find errors, and get suggestions for MySQL, PostgreSQL, SQL Server, Oracle, and SQLite.
Validation Options
Select your database type for dialect-specific checks
Enable additional validation checks
SQL Code to Validate
Validation Results
0 IssuesValidation results will appear here...
Click "Validate SQL" to check your code for errors and suggestions
SQL Validator Tool – Check Syntax & Find Errors
The SQL Validator Tool helps you identify syntax errors, common mistakes, and potential issues in your SQL queries before executing them against your database.
What the Validator Checks
- Syntax Errors – Basic SQL syntax validation
- Unmatched Characters – Quotes, parentheses, brackets
- Common Typos – Misspelled keywords (FRMO, WHRE, etc.)
- JOIN Conditions – Missing ON clauses in JOIN operations
- Dialect-Specific Issues – Database-specific syntax validation
- Performance Hints – Suggestions for query optimization
- Best Practices – Coding standards and conventions
Supported Database Dialects
- MySQL – Full support with MySQL-specific checks
- PostgreSQL – Advanced PostgreSQL features validation
- SQL Server – T-SQL syntax and Microsoft-specific features
- Oracle – PL/SQL and Oracle-specific syntax
- SQLite – Lightweight database validation
- ANSI SQL – Standard SQL compliance checking
Common Errors Detected
- Missing or extra commas in SELECT lists
- Unclosed string literals
- Mismatched parentheses in complex expressions
- Missing table aliases in JOIN operations
- GROUP BY clause issues
- HAVING clause without GROUP BY
- LIMIT/OFFSET without ORDER BY
When to Use the SQL Validator
- During Development – Catch errors early in the coding process
- Code Reviews – Quickly validate SQL in pull requests
- Learning SQL – Get immediate feedback on practice queries
- Migration Projects – Validate SQL when moving between databases
- Production Preparation – Final check before deploying queries
Limitations
This validator performs static analysis and cannot:
- Connect to live databases
- Validate table/column existence
- Check data types or constraints
- Execute queries for result validation
- Perform comprehensive security auditing
Always test important queries against your actual database with representative data.
Security & Privacy
All validation happens in your browser. No SQL code is sent to any server, ensuring complete privacy and security for your database queries.
Frequently Asked Questions
The validator checks for syntax errors, unmatched quotes/parentheses, common typos, dialect-specific issues, missing JOIN conditions, and potential performance problems.
We support MySQL, PostgreSQL, SQL Server, Oracle, SQLite, and ANSI SQL. Each dialect has specific validation rules and suggestions.
No, this is a static analysis tool. It checks syntax and patterns but doesn't connect to databases or execute queries. For full validation, you should test queries against your actual database.
Errors indicate syntax problems that will likely cause query failure. Warnings suggest potential issues or best practice violations that might not break the query but could cause problems.
Basic checks are performed for obvious patterns, but this is not a comprehensive security scanner. Always use parameterized queries and proper security practices in production.
The validator catches common errors and patterns but cannot guarantee 100% accuracy. Always test important queries against your actual database system.
