Facebook login without registration. Possible?

Is it possible to integrate facebook login without any registration into my site? The reas开发者_如何学Goon I would like to do this is because I do not want to store any private user data such as password on my database. Is this entirely possible? I've searched the internet for such tutorial but unfortunately most of it requires user to register. Thanks

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Maybe use OpenID. You will only need to store some url (its like id). You can find more here: Facebook Supports OpenID for Automatic Login

But since no one knows if that works, try this: http://developers.facebook.com/docs/authentication/

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You can use it. However, you need to store the facebook sessionid of the user in your database.

If you dont want to identify the user next time, you can avoid saving the sessionid also.