MySQL 5.7 Reference Manual Including MySQL NDB Cluster 7.5 and NDB Cluster 7.6 Using Symbolic Links for MyISAM Tables on Unix

Symlinks are fully supported only for MyISAM tables. For files used by tables for other storage engines, you may get strange problems if you try to use symbolic links. For InnoDB tables, use the alternative technique explained in Section, “Creating Tables Externally” instead.

Do not symlink tables on systems that do not have a fully operational realpath() call. (Linux and Solaris support realpath()). To determine whether your system supports symbolic links, check the value of the have_symlink system variable using this statement:

SHOW VARIABLES LIKE 'have_symlink';

The handling of symbolic links for MyISAM tables works as follows:

These table symlink operations are not supported: