Should the mysqli
extension be enabled then on the very same phpinfo
page a “MysqlI Support | enabled” table header should appear. Look for that:
If you want to find out in a script, look for a function specific for mysqli like mysqli_connect()
and than check if it exists:
var_dump(function_exists('mysqli_connect'));
If this outputs FALSE, then it does not exists and it’s highly likely that you can not use the module.