Show/Hide Featured Image or replace it with custom field [closed]

I’m pretty sure you want something like this:

$myfield = get_post_meta($post->ID, 'short', true);

if ($myfield) {
  echo do_shortcode($myfield);
} else {
  the_post_thumbnail();
}

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