I tried to utilize C# provider for Mongo(http://mongodb.github.io/mongo-csharp-driver/2.2/getting_started/installation/) to filter the records stored in Analytics database of Sitecore 8.0 instance.

Here is the code snippet. For some reason, the filter does not work because the number of documents (>2k) are same before and after applying the filter. However, I expect only one record (see the second screenshot).

Your suggestion would be much appreciated!