What is responsible for triggering “robots-template.php” file or “wp_robots_noindex()” core function out of it?

What is responsible for triggering “robots-template.php” file or “wp_robots_noindex()” core function out of it?

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)