Switch Blogger To WordPress Without Losing any Single Page View

Permalink Structure

/%year%/%monthnum%/%postname%.html

functions.php Code

function wpb_update_slug() { 
global $wpdb;
$result = $wpdb->get_results("SELECT post_id, meta_value FROM $wpdb->postmeta WHERE meta_key = 'blogger_permalink' ");
$wpdb->print_error();
foreach ($result as $row){
$slug = explode("/",$row->meta_value);
$slug = explode(".",$slug[3]);
$wpdb->query("UPDATE $wpdb->posts SET post_name ='$slug[0]' WHERE ID = '$row->post_id' ");
}
echo "All Done..";
}