Sleep(5)#: {keyword}');select

: This attempts to prematurely close the original, legitimate SQL query statement intended by the developers [2].

: This is a comment character in MySQL. It tells the database to ignore the rest of the original SQL statement, ensuring the injected command doesn't cause a syntax error [1]. Purpose: Blind SQL Injection {KEYWORD}');SELECT SLEEP(5)#

Strict validation should be used to ensure input matches expected formats (e.g., integers only, no special characters). : This attempts to prematurely close the original,

If the payload works, an attacker can replace SLEEP(5) with more complex queries (e.g., IF(SUBSTRING((SELECT password FROM users),1,1)='a', SLEEP(5), 0) ) to extract data character-by-character based on whether the server pauses [3]. Security Implications IF(SUBSTRING((SELECT password FROM users)