在Mac上启动不了Mysql
版本如下：

OS: Mac OS X 10.6.4
MySql: mysql-5.5-osx10.6-x86.dmg

在Macbook上安装Mysql过程没问题，可是重启后问题就来了，弹出窗口说：

Insecure Startup Item disabled.
“/Library/StartupItems/MySQLCOM” has not been started because it does not have the proper security settings.

而且不光在System Preferences里面启动不了Mysql，就连输入command “sudo /Library/StartupItems/MySQLCOM start”，也没有丝毫启动的意思。

执行mysql -uroot -p 会报错

ERROR 2002 (HY000): Can’t connect to local MySQL server through socket ‘/tmp/mysql.sock’ (2)

原因是根本没启动mysql，后来又更改/tmp的权限还是不起作用。

终于

sudo /usr/local/mysql/bin/mysqld_safe
通过这种古老的方法，第一次可以启动了。

还是心有不甘，遍寻了google，折腾了将近3个小时才找到答案,url[http://discussions.apple.com/thread.jspa?messageID=12781385&tstart=0]。答案就是

“It is a bug!”

Riquez说:

I began to think that mysql 5.5 is just not playing well with OS 10.6.5.

ekkedesig说:

It is clear that MySQL 5.5 distribution from mysql.com is aimed at OS X Server edition, and is very problematic for the regular desktop version.

按照Riquez的方法卸载mysql5.5

sudo rm /usr/local/mysql
sudo rm -rf /usr/local/mysql*
sudo rm -rf /Library/StartupItems/MySQLCOM
sudo rm -rf /Library/PreferencePanes/My*
edit /etc/hostconfig and remove the line MYSQLCOM=-YES-
sudo rm -rf /Library/Receipts/mysql*
sudo rm -rf /Library/Receipts/MySQL*
sudo rm -rf /var/db/receipts/com.mysql.*
重新下载了mysql-5.1.54-osx10.6-x86.dmg

安装，重启，成功！