I was wondering how to formulate a query to just get a single instance
of a value as opposed to every instance.
Concretely, in keeping with the twitter and tweet case, the scenario
would be when a user wants to search who s/he has mentioned in tweets.
How many times the other user has been mentioned or the tweets where
they were mentioned is not important. Is there a filter that could do
this or do you have to parse through every search result and instance
to derive this info?