title: correct htaccess query string code
body: <p>Is this the correct code for my HTACCESS to setting up header to noindex nofollow </p>
  
  <pre><code> RewriteCond %{QUERY_STRING} (^|&amp;)cart? [NC]
  
   RewriteRule .* - [E=MY_SET_HEADER:1]
  
   Header set X-Robots-Tag "noindex, nofollow" env=MY_SET_HEADER
  </code></pre>
  
  <p>so that the following URL cannot be indexed by search engines.</p>
  
  <p><a href="http://www.mysite.com/cart?qty=1&amp;id_product=8&amp;token=7775324f4cd8c884155af53ca90e44ad&amp;add" rel="nofollow">http://www.mysite.com/cart?qty=1&amp;id_product=8&amp;token=7775324f4cd8c884155af53ca90e44ad&amp;add</a></p>
  
  <p>Actually moz analytics crawling these types of URL which is in 
  <code>&lt;a href="http://www.mysite.com/cart?qty=1&amp;id_product=8&amp;token=7775324f4cd8c884155af53ca90e44ad&amp;add"&gt;Add To Cart&lt;/a&gt;</code></p>
  
  <p>as a duplicate page content. Dont know why as these URL are just a Add to cart URL and these are nothing to do with any content.</p>
  
  <p>Also I need suggestion for any online tutorial on playing with htaccess .</p>
  
  <p>Thanks.</p>