Making Dynamic URLs Static
or how to have a database driven site with no query strings appearing in the urls

The method used on this site relies on an asp custom 404 error page (it needs to be set as a URL, not a file). I first heard of this technique at 4 Guys From Rolla in an article describing how it was used to manage redirects of about 6000 pages when the msdn.microsoft.com site was restructured. I have also drawn on other sources so I claim no credit for any originality on my part!

The error handler first analyses the url request and only then executes the necessary database query. The important snippet of asp code looks something like this:-

' step one grab the identity of the page from the query sent to the 404 page:-
strOrigURL = lcase(request.servervariables("QUERY_STRING") )

' step two check if it meets your criteria or is a genuine 404, in my case, I just wanted to check that the page requested belonged to a particular directory and had a numeric name.

if instr(strOrigURL,"/cinereviews/") >0 then

' step three - collect the numeric id requested

intStart = instr(strOrigURL,"/cinereviews/") + 13
intReview = replace(mid(strOrigURL,intStart),"/","")

' step 4 go fetch the record from the database in the usual way

mySQL = "select * from Reviews where id=" & intReview %>
This technique can be used to build whole sites, power a CMS or just serve pages within one directory.

Do test thoroughly that the page when served returns a 200 ok code to the browser since search engines will choke on 304 or 404 codes. It should do, but it is worth checking.

Your page usage stats will probably be confused by this technique so it is worth setting up an additional script to analyse details of the requests for your custom 404 page.

You can adapt this technique so that it uses a proper name for pages instead of the numeric ID which I use. In my case I was concerned to ensure that the page names were always unique and the obvious field in my database (the Movie Title) did not, on its own, ensure that this would always be the case. There are benefits in having a meaningful url since some search engines use the url in their ranking algorithm.

The detail of what you will need to add to your code will vary according to your application, but I hope I have described the principle adequately. Good luck and let me know if you need more information.

Tim Marchant

* PhpWiki will try to use short urls to pages, eg
*http://www.example.com/index.php/HomePage
* If you want to use urls like
*http://www.example.com/index.php?pagename=HomePage
* then define 'USE_PATH_INFO' as false by uncommenting the line below.
* NB: If you are using Apache >= 2.0.30, then you may need to to use
* the directive "AcceptPathInfo On" in your Apache configuration file
* (or in an appropriate <.htaccess> file) for the short urls to work:
* Seehttp://httpd.apache.org/docs-2.0/mod/core.html#acceptpathinfo

mvandam wrote:
I have heard that a quite portable (i.e. works on many web servers) way to rewrite the URLs is something like:

http://example.com/index.php/articles/1/

(Note the presense of 'index.php'.)

I first saw this done in 'phpwiki'. Here is a little excerpt from the comments of the file index.php (in phpwiki):

Quote:

* PhpWiki will try to use short urls to pages, eg
*http://www.example.com/index.php/HomePage
* If you want to use urls like
*http://www.example.com/index.php?pagename=HomePage
* then define 'USE_PATH_INFO' as false by uncommenting the line below.
* NB: If you are using Apache >= 2.0.30, then you may need to to use
* the directive "AcceptPathInfo On" in your Apache configuration file
* (or in an appropriate <.htaccess> file) for the short urls to work:
* Seehttp://httpd.apache.org/docs-2.0/mod/core.html#acceptpathinfo