I have a function that contains a wpdb query. It’s supposed to get the image alt text, based on the url of the image. This is the function:

// retrieves the attachment alt from the file URL
function get_image_alt_from_url($image_url) {
  global $wpdb;
  $id = $wpdb->get_col($wpdb->prepare("SELECT ID FROM $wpdb->posts WHERE guid='%s';", $image_url ));
  if ($id) {
    return get_post_meta($id[0], '_wp_attachment_image_alt', TRUE);
  }
  return false;
}

It used to work, but now it returns false every time. Upon debugging the function, I found that the $id variable is null.

I wonder if this has anything to do with upgrading PHP to 8.0, and if so, how to get around it. It still works on my local site, so I doubt it’s related to a wp core update.

WordPress: 6.2.2
PHP: 8.0
Hosted on Kinsta

Thank you so much for your help,

Jill