I have used fb_graph gem but found it insufficient. There are several Ruby gems for facebook by the way. I suggest using koala. Koala supports OAuth, REST API and the recommended Graph API.

Add the gem on your Gemfile if you are using Rails 3 or Sinatra with bundler.

gem 'koala'

To retrieve Facebook comments for a site, it is quite simple. Just query or get all xid's on comments_info table and when you get all xid's, you can select the comments. The query looks like SQL. FQL is actually less than SQL (LIKE is not supported).

@rest = Koala::Facebook::RestAPI.new(token)
@all_comments = @rest.fql_query("SELECT id, fromid, xid, text, time from comment WHERE xid IN (#{@comments_ids.join(",")})")
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Hello! I am Kat. I've been a developer for several years. When I'm not sitting down, reading and working for long hours, I am traveling to some place of interest.
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