Obtain all comments posted to a Facebook social comments page using FQL

Is there a way to use FQL to obtain the XID of all comments posted on any page associated with a particular Facebook application ID?

The docs listed for FQL on the comments_info table at this address seem to suggest that it is possible:

http://developers.facebook.com/docs/reference/fql/comments_info/

If I attempt the following query however, it returns no results.

SELECT xid FROM comments_info WHERE app_id = {MY_APP_ID}

I want to use this to find the most popular pages without individually checking each URL to determine which one has the most posts.

If you are trying to get comments from the Comments plugin, try the comment FQL table instead. Legacy fb:comments were auto-migrated to the latest version a while ago, effectively rendering *comments_info* obsolete.

From the *comments_info* docs page: "Note: This table contains a mapping of app_id to XIDs used by legacy fb:comments. It does not contain a map for the current comments plugin, which does not use XIDs."