Using Symbolic Links 8.12.2.3 Using Symbolic Links for Databases on Windows •If you are not using symlinks, start  mysqld  with the  --skip-symbolic-links  option to ensure that no one can use  mysqld  to drop or rename a file outside of the data directory. • ALTER TABLE  ignores the  DATA DIRECTORY  and  INDEX DIRECTORY  table options. •If you use  ALTER TABLE ... RENAME  or  RENAME TABLE  to move a table to another database, the table is moved to the other database directory. If the table name changed, the symlinks in the new database directory are renamed to the new names and the data file and index file are renamed accordingly. •If you rename a table with  ALTER TABLE ... RENAME  or  RENAME TABLE  and you do not move the table to another database, the symlinks in the database directory are renamed to the new names and the data file and index file are renamed accordingly. • myisamchk  does not replace a symlink with the data file or index file. It works directly on the file to which the symlink points. Any temporary files are created in the directory where the data file or index file is located. The same is true for the  ALTER TABLE ,  OPTIMIZE TABLE , and  REPAIR TABLE  statements. •To instruct a running MySQL server to perform the symlinking, use the  DATA DIRECTORY  and INDEX DIRECTORY  options to  CREATE TABLE . See Section 13.1.20, “CREATE TABLE Statement” . Alternatively, if  mysqld  is not running, symlinking can be accomplished manually using  ln -s  from the command line. •You can symlink the data file and the index file independently to different directories. •In the data directory, you always have the data ( .MYD ) file and the index ( .MYI ) file. The data file and index file can be moved elsewhere and replaced in the data directory by symlinks. These table symlink operations are not supported: On Windows, symbolic links can be used for database directories. This enables you to put a database directory at a different location (for example, on a different disk) by setting up a symbolic link to it. Use of database symlinks on Windows is similar to their use on Unix, although the procedure for setting up the link differs. Suppose that you want to place the database directory for a database named  mydb  at  D:\data\mydb . To do this, create a symbolic link in the MySQL data directory that points to  D:\data\mydb . However, before creating the symbolic link, make sure that the  D:\data\mydb  directory exists by creating it if necessary. If you already have a database directory named  mydb  in the data directory, move it to  D:\data . Otherwise, the symbolic link has no effect. To avoid problems, make sure that the server is not running when you move the database directory. The path used with either or both of the  DATA DIRECTORY  and  INDEX DIRECTORY  options may not include the MySQL  data  directory. (Bug #32167) When you drop a table that is using symlinks,  both the symlink and the file to which the symlink points are dropped . This is an extremely good reason  not  to run  mysqld  as the  root  operating system user or permit operating system users to have write access to MySQL database directories. Note Note 1834 The handling of symbolic links for  MyISAM  tables works as follows: