search filter add priority to post_type and add order to some post_type

Here is the code from the provided link after adaptation.

add_filter( 'posts_orderby', 'se344727_custom_search_order', 10, 2 );
function se344727_custom_search_order( $orderby, $query )
{
    global $wpdb;

    if (!is_admin() && $query->is_main_query())
    {
        if ($query->is_search) 
        {
            // -- sort by: type, title, date --
            // " ELSE 2 END ASC, " . $orderby;

            // -- sort by: type, date --
            // " ELSE 2 END ASC, {$wpdb->prefix}posts.post_date DESC;

            $orderby =
                " CASE WHEN {$wpdb->prefix}posts.post_type="page" THEN 1 " . 
                " ELSE 2 END ASC, " .
                $orderby;
        }
    }    
    return $orderby;
}