Uninstalling MySQL on Mac OS X Leopard

To uninstall MySQL and completely remove it (including all databases) from your Mac do the following:

• Use mysqldump to backup your databases to text files!
• Stop the database server
• 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-
• rm -rf ~/Library/PreferencePanes/My*
• sudo rm -rf /Library/Receipts/mysql*
• sudo rm -rf /Library/Receipts/MySQL*

The last two lines are particularly important as otherwise, you can't install an older version of MySQL even though you think that you've completely deleted the newer version!

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