Can it detect SQL syntax errors and performance bottlenecks?

Yes, it can. The AI analyzes your query to instantly identify syntax mistakes, inefficient joins, and potential performance issues due to missing indexes, suggesting immediate improvements.

Does it support different database dialects like MySQL and PostgreSQL?

Yes, it supports major DBs including MySQL, PostgreSQL, Oracle, and SQL Server. It performs syntax checks tailored to the selected dialect and suggests corrections if functions from another DB are mistakenly used.

Can it check for security vulnerabilities like SQL Injection?

Yes. It features a security audit that warns against dangerous practices like direct concatenation of user input into queries. It also provides secure alternatives using placeholders (Prepared Statements).

Is there a feature to beautify and format the code?

Yes. The tool automatically formats the input SQL into clean, professional code by capitalizing keywords and applying standard indentation. The formatted code is ready for direct copy-paste.

SQLChecker

AI SQL Review Tool

Get your query reviewed by a professional AI.
From syntax error detection to performance improvement, AI provides instant suggestions.

First, select the explanation level!
- 🔰 Beginner: Explains gently, avoiding jargon, as a senior peer would teach a junior.
- 🤖 Pro: Uses technical terms and focuses on design philosophy and performance from an advanced perspective.
Paste your SQL query to be reviewed in the input box below.
Tip: Including your Table Structure (CREATE TABLE statement) drastically improves accuracy!
This allows the AI to understand column and index information precisely for more advanced performance suggestions.

Database:

✨ Formatted Code

-- Your formatted code will appear here after review

📝 Quick Diagnosis Result

AI's quick diagnosis will be displayed here.

AI's detailed analysis result will be displayed here.

SQL Syntax Check, Format, and Tuning All-in-One

SearchCode Pro's "AI SQL Checker" is an integrated review tool for engineers that goes beyond simple syntax error detection. It offers an **SQL Formatter** to enhance readability and provides **Performance Tuning** suggestions to improve query speed.

Full Support for Major Database Dialects

SQL syntax differs slightly between database products (dialects). Our tool also performs dialect checks, and the AI appropriately reviews by understanding the characteristics of each.

MySQL / MariaDB

Accurately diagnoses MySQL-specific syntax errors (Error 1064, etc.) like LIMIT clauses, backtick escaping, and unique date functions.

Oracle Database

Analyzes Oracle-specific notations like PL/SQL blocks, the NVL function, and addresses causes of ORA errors.

PostgreSQL

Supports PostgreSQL-specific writing mistakes, such as strict type casting (::), window functions, and JSON operations.

SQL Server (T-SQL)

Performs checks based on T-SQL unique rules, including TOP clauses, DATEADD, and bracket [] escaping.

Specific SQL Error Cases Solved by AI

Shorten the time spent searching for the mistake when "Syntax Error" appears in the console. The AI instantly finds the following mistakes that beginners often fall into.

5. 🛡️ SQL Injection Vulnerability Diagnosis

Automatically checks for dangerous practices (like direct string concatenation of user input) that could lead to SQL Injection. It points out vulnerabilities and suggests secure correction examples using placeholders (Prepared Statements).

1. Full-width Space / Invisible Character Contamination

A full-width space that looks like a blank space in the editor can cause an error during SQL execution. Our checker automatically detects these "invisible errors" and suggests deletion.

2. Mismatched Parentheses and Comma Errors

Points out errors easily missed by eye, such as forgetting closing parentheses in nested subqueries or having an unnecessary trailing comma in the SELECT clause.

3. Missing GROUP BY Specification

Prevents errors that occur when using aggregate functions (COUNT, SUM, MAX, etc.) by checking that all non-aggregated columns are included in the GROUP BY clause.

4. N+1 Issues and Inefficient Join Warnings

For practices that are syntactically correct but severely degrade performance (like non-indexed LIKE searches or unnecessary DISTINCT usage), the tool provides suggested improvements (best practices).

Common SQL Syntax Errors and Causes

When SQL doesn't work, the cause is often a simple syntax error. Here are common errors frequently encountered by beginners and their solutions.

1. Missing or Extra Commas

A mistake where a comma is left after the last column name in a SELECT clause, or conversely, forgotten entirely.

-- Mistake (Comma at the end)
        SELECT id, name, email, FROM users;

        -- Correct
        SELECT id, name, email FROM users;

2. GROUP BY Specification Error

When using aggregate functions like COUNT or SUM, all columns specified in SELECT (other than the aggregate function) must be included in GROUP BY.

3. Full-width Space Contamination

The code may contain full-width spaces which are invisible but cause errors. Our SQL checker can instantly detect these "invisible errors."

4. Use of Reserved Words

Using words already defined in SQL (reserved words) like ORDER or USER as table or column names can cause errors. In such cases, they must be enclosed in backticks, like `user`.