Remove mysql 5.6.26-community

To uninstall all files/packages installed by the shell script simply undo all commands executed in the script logged in with an admin account:

1. Open System Preferences -> MySQL and stop the service if it's running
2. Open the folder /Applications and drag SequelPro - if it was installed - to your trash.
3. Open Terminal and enter sudo rm -R /usr/local/mysql-5.6.26-osx10.8-x86_64 to remove the mysql folder
4. Enter sudo rm /usr/local/mysql to remove the soft link
5. Enter cd /Library/LaunchDaemons && ls
6. Search for the *.mysql.plist (the launch daemon plist of mysql) and remove it with sudo rm com.oracle.oss.mysql.mysqld.plist.
7. Remove the my.cnf file with sudo rm /etc/my.cnf
8. Remove the mysql socket soft link and the superior folder with sudo rm -R /var/mysql
9. Remove all installed mysql package receipts with sudo pkgutil --forget package-id.
   Example: sudo pkgutil --forget com.mysql.launchd The name of the other two packages are com.mysql.mysql and com.mysql.prefpane
10. Remove the file MySQL.prefPane in /Library/PreferencePanes/
11. Finally cd to /usr/local/bin and check the existence as well as the creation/modification date of the file pidof. Remove it if both dates match with the installation date of mysql.

Addendum

To remove the MySQL installation from System Info -> Software -> Installations (which is a "cosmetic problem" only) remove the MySQL dict entry:

<dict>
    <key>date</key>
    <date>2015-10-13T15:06:35Z</date>
    <key>displayName</key>
    <string>MySQL 5.6.26-community</string>
    <key>displayVersion</key>
    <string></string>
    <key>packageIdentifiers</key>
    <array>
        <string>com.mysql.mysql</string>
        <string>com.mysql.prefpane</string>
        <string>com.mysql.launchd</string>
    </array>
    <key>processName</key>
    <string>installer</string>
</dict>

by editing the file InstallHistory.plist in /Library/Receipts/ with sudo nano /Library/Receipts/InstallHistory.plist or with TextWrangler.