MongoDb, how to save data available in 3 different files

I am trying to work on movi开发者_如何学JAVAe recommendation as part of my learning and found dataset on Grouplens (http://www.grouplens.org/system/files/ml-data.tar__0.gz), but the data is distributed in

3 different files :

Ratings : UserID::MovieID::Rating::Timestamp  
Users : UserID::Gender::Age::Occupation::Zip-code  
Movies : MovieID::Title::Genres  

I want to save the data in MongoDB, so shall I merge these data into one document?

Please let me know

Thank you

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Well..i see no problem is merging them together...Having all the info in a single document will improve performance..And that is one of the reasons Document oriented databases are liked these days.. Nesting information is encouraged. You don't have fixed schema.. And you can nest information within information. This is something you can't do easily using mysql. So go ahead, join them all up in a single collection. p.s. do pass me the db dump if you don't mind :)