When using a few different Unix environments for development, the location of the socket for MySQL tends to vary quite a bit. Having to keep your database config different from the tree is a pain.

Luckily, there is a neat, but not widely known fix for this issue. It turns out that the YAML files used for Rails configuration are actually passed through the ERB. Now I can use this and it works without modification:

development:
  adapter: mysql
  database: development
  username: root
  password:
  host: localhost
  socket: <%=
     ['/opt/local/var/run/mysql5/mysqld.sock', # darwinports
      '/opt/local/var/run/mysqld/mysqld.sock', # darwinports, again
      '/var/run/mysqld/mysqld.sock',           # ubuntu/debian
      '/tmp/mysql.sock'].select { |f| File.exist? f }.first %>

yes, I know this isn’t mindblowing, but seriously… in the real world of development… isn’t it nice to get rid of the nits that pile up and frustrate everyone.