How does Google handle variables?

Is?foo=123&bar=4 treated the same as?foo=123&bar=555

[ThatAdamGuy]

I'm trying to help out a developer of some photo gallery software determine the best way to make his software compatible with AdSense.

He's really needs to know some details of how AdSense interprets URLs.

Specifically, he wants to know if:

somesite.com/photos.php?photo=123&othervar=555
...will be treated the same as
somesite.com/photos.php?photo=123&othervar=999

Actually, he and I would both love to know whether this'll flummox the MediaBot and *ALSO* whether this'll cause PageRank diffusion issues (e.g., if some link to the first URL and others link to the second URL). With practically identical content, will this dilute PR? Will this trigger a duplicate page penalty?

The reason why 'othervar' is there at all is to maintain the state of navigation... that is, to note whether a visitor is looking at the pic of me and Christiana in the "Adam" Gallery or the "Christiana" gallery, and provide next pic / previous pic functionality appropriately.

Thanks in advance for any insight you have into this!
(and is something that would be useful to directly e-mail as a question to AdSense staff or even Webmaster at Google.com?)

[JasonHamilton]

I've found that it goes by exact url.

That is why session IDs are frowned upon, since then one page will be seen as an infinite number of pages by the mediabot.

So in the example you gave, they are two separate pages.

[james007]

I rewrote my site to use 'fake' URLs - i.e. instead of using widgets.com/detail.php?id=542 it now uses widgets.com/small/blue/542

This gives Google more help, but also looks rather a lot more friendly, don't you think?

You can do this using a custom 404 error page.

[Jenstar]

Do a search for other sites using their software and see if there seem to be any issues with the URLs getting spidered. Usually, two variables are okay, but longer variable strings can sometimes cause problems.