SQL Syntax Checker
Validate your SQL queries with our free online syntax checker. No data is sent to our servers, all validation is done in your browser.
SQL Dialect
Try one of these examples based on the Sakila database:
SQL Query
Frequently Asked Questions
Our SQL syntax checker supports the following SQL dialects:
- MySQL
- PostgreSQL
- SQLite
- SQL Server (T-SQL)
- Oracle
Each dialect has its own specific syntax rules and extensions that our parser recognizes.
Yes, your data is completely secure. All validation happens entirely in your browser - we never send your SQL queries to our servers. This means your database schemas, table names, and query logic remain private and secure.
Our SQL syntax checker can detect a wide range of syntax errors, including:
- Missing or misplaced keywords
- Incorrect JOIN syntax
- Missing commas between columns
- Unbalanced parentheses
- Invalid table or column references
- Incorrect use of operators
- Malformed subqueries
Note that this tool only checks syntax, not semantic correctness. It cannot verify if tables or columns actually exist in your database.
An Abstract Syntax Tree (AST) is a tree representation of the abstract syntactic structure of your SQL query. Each node of the tree represents a construct in the SQL code.
When our parser processes your SQL query, it breaks it down into this tree structure, which makes it easier to analyze and validate. The AST shows how different parts of your query relate to each other hierarchically.
Visualizing the AST can help you understand how the database will interpret your query and can be useful for debugging complex queries.
Yes! Since all validation happens in your browser, you can use this tool offline after the initial page load. You can also download the Chat2DB desktop application for a fully offline experience with additional features.
There are several possible reasons:
- You might be using database-specific extensions or functions that our parser doesn't recognize
- Different databases have different levels of SQL standard compliance
- Some databases are more forgiving of syntax errors than our strict parser
- You might be using a newer feature that our parser hasn't been updated to support yet
If you encounter a query that works in your database but doesn't validate here, please let us know so we can improve our parser.
About This SQL Syntax Checker
Our SQL syntax validator helps you identify syntax errors in your SQL queries before you run them against your database. This tool supports multiple SQL dialects including MySQL, PostgreSQL, SQLite, and more.
Features
- Multi-dialect support: Validate against different SQL flavors
- Syntax highlighting: Makes your SQL more readable
- Privacy-focused: All validation happens client-side in your browser
- AST visualization: See how your SQL is parsed into an Abstract Syntax Tree
Example Queries
This example showcases how Chat2DB enables seamless schema synchronization from MySQL to PostgreSQL. We are using the Sakila sample database — a standard MySQL dataset that models a DVD rental store, containing tables for films, actors, customers, rentals, and more. 💡 Chat2DB automatically generates PostgreSQL-compatible DDL statements based on the MySQL schema. The UI allows you to: Select the source (MySQL) and target (PostgreSQL) databases Preview and execute the translated CREATE TABLE statements Preserve data types, constraints, and column comments.
Chat2DB: The Modern Database Tool
Intuitive interface with dark mode support
A modern, easy-to-use database client for SQL developers and data analysts. Available for Mac, Windows, and Linux.
Key Features
"Chat2DB completely replaced my old SQL workflow. It's fast, intuitive, and makes database work enjoyable again."
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