Get links that friends have "liked" on facebook

I was wondering how to build a FQL query where i could receive links/urls of my app that an user's friends have liked. I got the link table which looks good but there i need 开发者_高级运维an object id, which i dunno how to retrieve for my urls.

You can get the object id from the object_url table. https://developers.facebook.com/docs/reference/fql/object_url/