Posted by Chris Keating, Manager, Natural Search
Recently, Google’s Webmaster Blog has been dealing with the subject of URL parameters. In the September 12th post, Google warns that storing tracking information in the URL, such as a session ID, can cause Google to index duplicate pages. Duplicate pages in the index can lead to:
Google works to pull duplicate content from the index, but you can help by “removing unnecessary URL parameters” and “keeping the URL as clean as possible.”
On the surface, the September 12th post seems to contradict the September 22nd post, which says to avoid rewriting dynamic URLs unless you’re “very diligent in removing all parameters that could cause problems.” Google says that if you leave your dynamic URLs alone, they’ll determine which parameters should be removed. But remember the September 12th post? Help Google by “removing unnecessary URL parameters” and keeping URLs clean. Confused?
All Google is really saying in their latest post is to refrain from recklessly removing parameters from your dynamic URLs in order to make them look static. The concept of “dynamic is bad, static is good” is indeed a false dichotomy, as Google explains.
But that does not mean that there’s not a proper place for URL rewrites. They are still useful when:
The search engine spiders are getting better at indexing pages that they’ve had trouble with in the past. But that doesn’t change the fact that your site has a distinct SEO advantage if you (carefully) make indexation easier for the spider. URL rewriting is still a valid and important technique.