Wondering how Facebook does the "Mutual friends" feature

Posted by Pierre on Stack Overflow See other posts from Stack Overflow or by Pierre
Published on 2010-03-29T09:30:24Z Indexed on 2010/03/29 9:33 UTC
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database

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database-design

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facebook

Hello,

I'm currently developing an application to allow students to manage their courses, and I don't really know how to design the database for a specific feature. The client wants, a lot like Facebook, that when a student displays the list of people currently in a specific course, the people with the most mutual courses are displayed first.

As an additional feature, I would like to add a search feature to allow students to search for another one, and displaying first in the search results the people with most mutual courses.

I currently use MySQL, I plan to use Cassandra for some other features, and I also use Memcached for result caching.

Thanks.

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