nginx dynamic url rewrite

I have such a request, will rewrite url to google's search site,
type http://mysite/search/search.html?t=laday gaga --> http://www.google.com/search?q=lady%20gaga
I donn't want to use other tools(php/java etc.) except nginx.
For a long time googleing, finally find how to setting nginx dynamic url rewrite :)

 location /search/ {
  root   /var/2hei.net/nginx;
  if ($args){
  rewrite ^/search/search.html "http://www.google.com/search?q=$arg_t?" last;
  }
 }

and '?' is very important, or the rewrite url will add append query string,
http://mysite/search/search.html?t=laday gaga --> http://www.google.com/search?q=lady%20gaga?t=lady%20gaga
we will get wrong rewrite url.
alse we can use $query_string
 if ($query_string ~* t=(.*)){
  ...
 }

Just enjoy it!