2.6.1.5 Distributing Data Across Different Disks on Windows

Beginning with MySQL Version 3.23.16, the mysqld-max and mysql-max-nt servers in the MySQL distribution are compiled with the -DUSE_SYMDIR option. This allows you to put a database on a different disk by setting up a symbolic link to it (in a manner similar to the way that symbolic links work on Unix).

On Windows, you make a symbolic link to a database by creating a file that contains the path to the destination directory and saving this in the data directory using the filename `db_name.sym', where db_name is the database name. Note that the symbolic link will not be used if a directory with the database name exists.

For example, if the MySQL data directory is `C:\mysql\data' and you want to have database foo located at `D:\data\foo', you should create the file `C:\mysql\data\foo.sym' that contains the text D:\data\foo\. After that, all tables created in the database foo will be created in `D:\data\foo'.

Note that because of the speed penalty you get when opening every table, we have not enabled this by default even if you have compiled MySQL with support for this. To enable symlinks you should put in your `my.cnf' or `my.ini' file the following entry:

[mysqld]
symbolic-links

In MySQL 4.0, symbolic links are enabled by default. If you don't need them, you can disable them with the skip-symbolic-links option.

User Comments

Has any one gotten symlinks to work on XP by using the my.ini file? If so how?
Thanks in advance.Alex

Add your own comment.