被一个小朋友问到,直接公布答案：
If your MySQL client/server version is a 5.6.x a way to avoid the WARNING message are using the mysql_config_editor tools:
mysql_config_editor set --login-path=local --host=localhost --user=username --password
Then you can use in your shell script:
mysql --login-path=local -e "statement"
instead of:
mysql -u username -p pass -e "statement"
Warning: Using a password on the command line interface can be insecure.解决办法
原文：http://www.cnblogs.com/paul8339/p/7266231.html