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Fatal error: Uncaught ValueError: mysqli::query(): Argument #1 ($query) cannot be empty in /users/balu52/www/Temperatur/save_einstellung.php:19 Stack trace: #0 /users/balu52/www/Temperatur/save_einstellung.php(19): mysqli->query('') #1 {main} thrown in /users/balu52/www/Temperatur/save_einstellung.php on line 19