I've been struggling with this for some time.
I've installed Rails 3, gem, mysql on my Snow Leopard machine. All was going well until I created my first project and tried to run
rails server
Upon running this I get:
jontybrook$ rails server
/Library/Ruby/Gems/1.8/gems/mysql2-0.2.6/lib/mysql2/mysql2.bundle: dlopen(/Library/Ruby/Gems/1.8/gems/mysql2-0.2.6/lib/mysql2/mysql2.bundle, 9): Library not loaded: libmysqlclient.16.dylib (LoadError)
Referenced from: /Library/Ruby/Gems/1.8/gems/mysql2-0.2.6/lib/mysql2/mysql2.bundle
Reason: image not found - /Library/Ruby/Gems/1.8/gems/mysql2-0.2.6/lib/mysql2/mysql2.bundle
from /Library/Ruby/Gems/1.8/gems/mysql2-0.2.6/lib/mysql2.rb:7
from /Library/Ruby/Gems/1.8/gems/bundler-1.0.7/lib/bundler/runtime.rb:64:in `require'
from /Library/Ruby/Gems/1.8/gems/bundler-1.0.7/lib/bundler/runtime.rb:64:in `require'
from /Library/Ruby/Gems/1.8/gems/bundler-1.0.7/lib/bundler/runtime.rb:62:in `each'
from /Library/Ruby/Gems/1.8/gems/bundler-1.0.7/lib/bundler/runtime.rb:62:in `require'
from /Library/Ruby/Gems/1.8/gems/bundler-1.0.7/lib/bundler/runtime.rb:51:in `each'
from /Library/Ruby/Gems/1.8/gems/bundler-1.0.7/lib/bundler/runtime.rb:51:in `require'
from /Library/Ruby/Gems/1.8/gems/bundler-1.0.7/lib/bundler.rb:112:in `require'
from /Users/jontybrook/Dropbox/CODING/simple_cms/config/application.rb:7
from /Library/Ruby/Gems/1.8/gems/railties-3.0.3/lib/rails/commands.rb:28:in `require'
from /Library/Ruby/Gems/1.8/gems/railties-3.0.3/lib/rails/commands.rb:28
from /Library/Ruby/Gems/1.8/gems/railties-3.0.3/lib/rails/commands.rb:27:in `tap'
from /Library/Ruby/Gems/1.8/gems/railties-3.0.3/lib/rails/commands.rb:27
from script/rails:6:in `require'
from script/rails:6
jontybrook$
As far as I can tell the problem is with the mysql2 gem. MySQL seems to be running fine and my Gemfile references mysql2, my database.yml file seems ok also.
The error mentions
Reason: image not found - /Library/Ruby/Gems/1.8/gems/mysql2-0.2.6/lib/mysql2/mysql2.bundle
And yet
jontybrook$ cd /Library/Ruby/Gems/1.8/gems/mysql2-0.2.6/lib/mysql2
jontybrook$ ls
client.rb em.rb error.rb mysql2.bundle result.rb
MySQL2.bundle is there!?
If I use the old mysql gem, WEBrick boots fine. But that's not ideal, is it?
I've tried everything google can give me! Any help much appreciated.
I was never able to get any of these answers to work for me, but this is the command that I used to make it work for me. This way you don't need to use install_name_tool every time you update your mysql
sudo ln -s /usr/local/mysql/lib/libmysqlclient.18.dylib /usr/lib/libmysqlclient.18.dylib