Hi @signalwarrant
I don’t think saving the total to the database is a good thing to do. It can add loads to your database and make your site slow. Instead, you can create a function to calculate it like this:
function totalMiles( $post_id ){
$miles = get_field('miles', $post_id);
$cars = get_field('cars', $post_id);
return $cars * $miles;
}
Then you can use it like this:
echo totalMiles(698);
If you still want to save it to the database, you need to do it with the acf/save_post hook and the update_field() function.
I hope this makes sense 🙂
