MAC install download good. GZ package (not like. DMG directly double-click on the line)

After downloading, unzip it and then hit the command in Terminal:

复制文件：蓝色部分为你解压文件的路径，直接拖到这里就行了
$ sudo mv mysql-5.1.45-osx10.6-x86_64文件路径 /usr/local/mysql

接下来切换到：
$ cd /usr/local
$ sudo chown -R mysql:mysql mysql
$ cd mysql
$ sudo scripts/mysql_install_db --user=mysql
$ sudo chown -R root .
$ sudo chown -R mysql data

Then CD bin with

$ sudo cd bin/

$ sudo ./mysql_secure_installation
To modify the root password, which is empty by default, is obviously less secure, and is then configured as appropriate, as the development environment is less restrictive.

$ sudo ./mysqld_safe
To start MySQL

$ sudo ./mysql -u root -p
Enter the root password you just set to log in to MySQL

$ sudo ./mysqld_safe stop
Stop MySQL

MAC install download good. GZ package (not like. DMG directly double-click on the line)