其实，这是一种规范，而不是一种规则。所以你使用驼峰来命名也是可以的，但是我们要避免用驼峰来命名。

不只是数据库，就是平常的程序也是，因为：

MYSQL 5.7 FEATURES. THIS MANUAL DESCRIBES FEATURES THAT ARE NOT INCLUDED IN EVERY EDITION OF MYSQL 5.7; SUCH FEATURES MAY NOT BE INCLUDED IN THE EDITION OF MYSQL 5.7 LICENSED TO YOU. IF YOU HAVE ANY QUESTIONS ABOUT THE FEATURES INCLUDED IN YOUR EDITION OF MYSQL 5.7, REFER TO YOUR MYSQL 5.7 LICENSE AGREEMENT OR CONTACT YOUR ORACLE SALES REPRESENTATIVE.

你能一眼看出这段文字么？

MySQL 5.7 features. This manual describes features that are not included in every edition of MySQL 5.7; such features may not be included in the edition of MySQL 5.7 licensed to you. If you have any questions about the features included in your edition of MySQL 5.7, refer to your MySQL 5.7 license agreement or contact your Oracle sales representative.

人看习惯了一种规范，看到驼峰就要花脑力去解析的好么？不只是要你看得懂，后面维护的人也要看懂。