Different locations for MySQL databases?

Can I configure MySQL to store a specific database in a separate place on disk?

I still want any new databases to go to the default location, but there's a specific database that I'd like to have stored in my Dropbox folder so that it can stay synced between a few computers.

How can I do this?


Of course you can! You have to grant root permisson. Read the ln manual pages.

MySQL stores the database data in separated dirs in /var/lib/mysql. I think, at first you had to make a dir, where you want to put the selected database's files. Grant root permisson, stop MySQL deamon:

# /etc/init.d/mysql stop

Copy your data to your new folder:

# cp /var/lib/mysql/DATABASENAME /path/to/new/database/dir

Remove your old dir from MySQL data files: (Warning! ALWAYS make SQL dump first!!!)

# rm -R /var/lib/mysql/DATABASENAME

Make a symlink back to MySQL data dir: (Pay attention! Read the man page of ln first!!!)

# ln -s /full/path/to/new/database/dir /var/lib/mysql/DATABASENAME

After it, you are ready, start your MySQL:

# /etc/init.d/mysql start

Warning! If your new dir isn't write- and readable by MySQL that wouldn't work! Example, the common problem: you place your new data dir to your home folder, your home folder is read protected by others(ex: drwxrwx--- you you yourdir).

Ask, if you want to know other things about that method!


Please bear in mind that if you are using Ubuntu, you need also to add an entry in the AppArmour configuration file /etc/apparmor.d/usr.sbin.mysqld otherwise you will keep getting writing permission errors even though you change files and folder permissions.