# SQL Injection Protection

SQL injection is one of the most common and dangerous security vulnerabilities in database applications. rhosocial ActiveRecord provides built-in protection against SQL injection attacks, but it's important to understand how these protections work and how to use them correctly.

## What is SQL Injection?

SQL injection occurs when untrusted user input is directly incorporated into SQL queries without proper validation or sanitization. This can allow attackers to manipulate the query's structure and potentially:

- Access unauthorized data
- Modify database content
- Delete database records
- Execute administrative operations on the database

## How rhosocial ActiveRecord Prevents SQL Injection

rhosocial ActiveRecord uses parameterized queries by default, which is the most effective way to prevent SQL injection. With parameterized queries:

1. The SQL statement structure is defined first with placeholders
2. The actual values are sent separately to the database
3. The database treats these values as data, not as part of the SQL command

### Example of Safe Query Construction

```python
# Safe: Using ActiveRecord's query methods
users = User.query().where('username = ?', (username_input,)).all()

# Safe: Using parameterized queries with raw SQL
users = User.query().backend.execute("SELECT * FROM users WHERE username = ?", (username_input,))
```

## Common Pitfalls to Avoid

### String Concatenation in Raw SQL

```python
# UNSAFE - vulnerable to SQL injection
query = f"SELECT * FROM users WHERE username = '{username_input}'"
users = User.query().backend.execute(query)

# SAFE - using parameterized queries
query = "SELECT * FROM users WHERE username = ?"
users = User.query().backend.execute(query, (username_input,))
```

### Dynamic Table or Column Names

When you need to use dynamic table or column names, rhosocial ActiveRecord provides safe methods to validate and escape these identifiers:

```python
# Note: Use the identifier escaping functionality provided by your database backend
# This is just an example, actual implementation may vary by backend
table_name = User.query().backend.dialect.escape_identifier(user_input_table_name)
query = f"SELECT * FROM {table_name} WHERE id = ?"
results = User.query().backend.execute(query, (id_value,))
```

## Best Practices

1. **Use ActiveRecord's Query Methods**: Whenever possible, use the built-in query methods like `query().where()`, `query().select()`, etc., which automatically use parameterized queries.

2. **Parameterize All User Input**: When using raw SQL, always use parameterized queries with placeholders (`?`) instead of string concatenation.

3. **Validate and Sanitize Input**: Even with parameterized queries, validate and sanitize user input according to your application's requirements.

4. **Use Prepared Statements**: For frequently executed queries, use prepared statements to improve both security and performance.

5. **Limit Database Permissions**: Apply the principle of least privilege to database users. Your application should use a database account with only the permissions it needs.

6. **Audit Your Queries**: Regularly review your code for potential SQL injection vulnerabilities, especially in areas using raw SQL.

7. **Keep ActiveRecord Updated**: Always use the latest version of rhosocial ActiveRecord to benefit from security improvements and fixes.

## Testing for SQL Injection

Regularly test your application for SQL injection vulnerabilities. Consider using:

- Automated security testing tools
- Manual penetration testing
- Code reviews focused on security

## Conclusion

SQL injection remains one of the most critical security threats to database applications. By leveraging rhosocial ActiveRecord's built-in protections and following best practices, you can significantly reduce the risk of SQL injection attacks in your application.

Remember that security is an ongoing process, not a one-time implementation. Stay informed about new security threats and regularly update your security practices.