: This is the core instruction for the database. It tells the server to pause for exactly 2 seconds before responding.
sql server - What is this hacker trying to do? - Stack Overflow
The string you provided is a specific type of cyberattack payload used to test for vulnerabilities. Specifically, it targets Microsoft SQL Server (MSSQL) databases. Breakdown of the Code
This technique is called "blind" because the database doesn't return actual data or error messages to the attacker's screen. Instead, the attacker observes the of the website: The attacker sends the request.
: This likely targets a field in a web application where the input "MEGA" is expected. The trailing single quote ( ' ) is intended to "break out" of the application's intended SQL query.
If the website takes exactly 2 seconds (or more) to load, the attacker knows the database is vulnerable to SQL commands.