Warning: Undefined variable $dbHost in /tmp/database.php on line 2

Fatal error: Uncaught TypeError: connectToDb(): Argument #1 ($dbHost) must be of type string, null given, called in /tmp/database.php on line 2 and defined in /tmp/database.php:5 Stack trace: #0 /tmp/database.php(2): connectToDb() #1 /www/wwwroot/umartd.zvvtw.com/index.php(10): require_once('...') #2 {main} thrown in /tmp/database.php on line 5