If you’re not inside WP then it will be extremely difficult to get what you’re looking for. It’s going to take some additional queries.
ACF stores only the attachment ID in a serialized array. You will first need to unserialize the array and then you will need to do queries to get the image URL.
If I was doing this inside of WP I would do something like this.
$image_array = maybe_unserialize(get_post_meta($post_id, 'gallery_field', true));
$count = count($image_array);
for ($i=0; $i<$count; $i++) {
$image = wp_get_attachment_src($image_array[$i], 'full');
$image_src = $image[0];
}
I am not familiar with exactly how you’d do that with SQL.
