mongodb/mongo — pull request #638 by sl33nyc (2014-02-18 15:06:43+00:00)
Title: SERVER-9790 Add this.$db || db.toString() to DBRef string representation

If the optional `$db` argument is specified in the [$DBRef](http://docs.mongodb.org/manual/reference/database-references/#dbrefs), prepend it before the collection name. Otherwise, prepend the current database before the collection name.