Warning: Undefined variable $db in C:\OpenServer\www\all.loc\core\libs\DB\query.php on line 20

Fatal error: Uncaught Error: Undefined constant "DEBUG" in C:\OpenServer\www\all.loc\core\ErrorHandler.php:29 Stack trace: #0 C:\OpenServer\www\all.loc\core\ErrorHandler.php(16): ErrorHandler->displayError() #1 [internal function]: ErrorHandler->exceptionHandler() #2 {main} thrown in C:\OpenServer\www\all.loc\core\ErrorHandler.php on line 29