Ruby on Rails, MAMP, MySQL, and OS X 10.6
I spent a very long time trying to get Ruby on Rails working with MAMP's MySQL on OS X 10.6. I was always getting this error message: $ rake db:migraterake aborted!uninitialized constant MysqlCompat::MysqlRes To eliminate the above error, my solution to the problem was simply: $ cd /usr/local/bin$ sudo mv ruby ruby.bak$ sudo ln -s /usr/bin/ruby ruby Now, to tell your application to use MAMP's MySQL server, just add the socket parameter to your database.yml file, as demonstrated here. I hope that helps. Read more