: This is a classic "tautology"—a statement that is always true. If an application is vulnerable to SQL injection, appending this string should result in the same output as just searching for the KEYWORD , because the AND condition is satisfied. Where You Might See This

In most cases, this specific string is . It is primarily used for detection rather than exploitation. Its goal is to confirm that the database is executing the injected code without actually deleting data or stealing credentials. However, it is a clear sign that someone (or something) is testing your system's security. SQL Keywords Reference - W3Schools

: Tools like Acunetix , Burp Suite , or OWASP ZAP generate these strings to probe for weak input validation.

The string appears to be a specialized input typically used in automated vulnerability scanning or SQL injection (SQLi) testing . Technical Purpose