best way to store 1:1 user relationships in relational database

Posted by aharon on Stack Overflow See other posts from Stack Overflow or by aharon
Published on 2010-05-26T01:00:00Z Indexed on 2010/05/26 1:01 UTC
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database-design

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relational-database

What is the best way to store user relationships, e.g. friendships, that must be bidirectional (you're my friend, thus I'm your friend) in a rel. database, e.g. MYSql?

I can think of two ways:

Everytime a user friends another user, I'd add two rows to a database, row A consisting of the user id of the innitiating user followed by the UID of the accepting user in the next column. Row B would be the reverse.
You'd only add one row, UID(initiating user) followed by UID(accepting user); and then just search through both columns when trying to figure out whether user 1 is a friend of user 2.

Surely there is something better?

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