网上很多方法都是：/usr/local/mysql/scripts/mysql_install_db --user=mysql 

但是很有可能报错，找不到bin目录中的my_print_defaults
错误信息： 
FATALERROR:Couldnotfind./bin/my_print_defaults
If you are using a binary release, you must run this script from
within the directory the archive extracted into. If you compiled
MySQL yourself you must run 'make install' first. 
       或
[root@bogon scripts]# /usr/local/mysql/scripts/mysql_install_db --user=mysql&
[1] 16874
[root@bogon scripts]#
FATAL ERROR: Could not find ./bin/my_print_defaults
If you compiled from source, you need to run 'make install' to
copy the software into the correct location ready for operation.
If you are using a binary release, you must either be at the top
level of the extracted archive, or pass the --basedir option
pointing to that location.
 
解决方法：
 [root@bogon scripts]# /usr/local/mysql/scripts/mysql_install_db --user=mysql --basedir=/usr/local/mysql --datadir=/usr/local/mysql/data &(这点非常重要)