I messed up my local install of MySQL (it's a long story that involves me almost throwing a punch to my 30" monitor). I finally gave up, deleted everything MySQL related according to these notes and then I used homebrew to do a clean install.
After the install I started getting this error:
ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/tmp/mysql.sock' (2)
I couldn't figure out what was going on so I checked my logs in /usr/local/var/mysql (in that directory find a file that ends in .err). Here's what I kept seeing over and over again:
110705 14:33:20 [ERROR] /usr/local/Cellar/mysql/5.5.12/bin/mysqld: unknown variable 'default-character-set=utf8' 110705 14:33:20 [ERROR] Aborting
Turns out if you upgrade MySQL you'll want to modify /etc/my.cnf. This line causes problems:
default-character-set = utf8
Remove that and you should be good. For reference here's what my '/etc/my.cnf' file looks like:
[mysqld] max_allowed_packet=64M collation-server = utf8_unicode_ci init-connect='SET NAMES utf8' character-set-server = utf8
As a side note be sure to change max_allowed_packet to something like 64M. I was trying to restore a large database and MySQL kept barfing with this error: ERROR 2006 (HY000) at line 682: MySQL server has gone away
Turns out the default packet size is to small to restore all but the smallest databases.