In my further development project, I implemented a multi-database integration, making multiple databases to work together in the Dudoj framework, as long as we specify a persistent class in the configuration file and the database where the query is in, do not need to pay for the bottom. What database is used, there are several databases, and we only need to call the persistence of the Dudoj framework to achieve the persistence and recovery of data, which greatly simplifies programming work. After completing these development work, I am thinking, if the user replaces the database, and the application does not need any changes, this is not a great enhancement of the adaptability of the user system. Then I repeatedly configured the entire framework and increased SQL function support, and tested on MySQL, SQL Server, DB2, PostgreSQL, Oracle9i, and all test passed. In fact, before implementing this feature, I can't determine this feature must be realized, because I don't know how big the difference is different, after all, I don't very proficient in other databases other than SQL Server, the initial period of achieving I have encountered some tricky problems, but I finally found a solution. My experience is that anything you don't try to actually do it, then you may never know the results, as long as you take out practical action efforts, then even if you finally fail, but you always know As a result, it is better than nothing. If I preliminary idea is just to solve the problem of persistent data, then the second step I think I think it is a problem that the company is running on the database platform. If Java makes our system write overce, run anywhere! Then the Dudoj framework enables enterprise applications to implement Write Once, Run Anywhere! Just the former Run Anywhere refers to the operating system, while the latter's Run Anywhere does not only refer to the operating system platform, but also refers to the database platform. After all, the vast majority of corporate applications are related to the database. To make the enterprise system to implement cross-database platform applications, general, programmers must write many targeted code, replace a database, must change the code, which brings a lot of trouble to system maintenance. Develop enterprise applications using Dudoj data persistence framework, allowing businesses to apply true to Write Once, Run Anywhere! This is also my idea, try my dream, I will always work hard to this, and now I have a certain implementation foundation.
