in the typical DB driven cms/ecommerce site you will have items pages at urls in some form similar to:
1) Is it good for SEO purpose to add a sort of description (related to page contents) in url? i.e.
even if descr key is not needed by the webapp to retrieve item from DB, thus making the url to work with/without the
descr key and to show the same identical page.
I'm asking because for instance my profile on Pro Webmasters seem exactly to do this:
They are the same url, the
marco-demaio value is not needed, only the
1429 value is needed to get my profile from DB.
NOTE: in this last example I think also url rewrite is involved, but this question goes beyond urls rewrite, I'm not interested in rewriting any url here and to whoever is an url-rewrite-addict I would suggest to read this Google official article.
2) Supposing the answer to (1) is yes or almost yes, do I need to do a redirect 301 (or use canonical)? And if yes from
http://...?id=36 or viceversa?
3) Supposing answer to (2) is "yes you better do redirect", why do I need a redirect (or canonical)? I mean do I even need redirect/canonical when I'm absolutely sure that my webapp will never link to both pages, so you will never find in the site the same page linked in two different ways (i.e. all link to id=36 will be in the form
http://...?id=36&descr=cheap-blue-jeans so why does Google should care about
http://...?id=36, I mean it should never get even indexed and therefor I should not ever have duplicated contents issues.
If you arrived here, thanks for the patience in reading into all this, and more thanks for any replies. :)