使用Derby数据库的注意事项

本人在移植Petstore到Derby数据库时碰到了很多问题，总结如下

1. User is a key word of Derby, So do not use "User" as table name or other object name
2. Can't use NULL as modifier of a field when creating a table
3. Primary key must use NOT NULL as modifier, elsewise can't create the primary key
4. Derby doesn't support tinyint type