Open-source object-oriented database db4o Tour (2)

At the same time, db4o is a feature of the management of the need DBA, occupied a very small resources, it is suitable for embedded applications, as well as Cache applications, it has since released db4o quickly attracted a large number of users will be db4o used in a variety of embedded systems , including mobile software, medical equipment and real-time control systems.

Db4o from Silicon Valley, California open-source database company db4objects responsible for the development and commercial operations and support. Db4o is based on the GPL. Db4objects in 2004, the CEO Christof Wittig, under the leadership of composition, funding background includes Mark Leslie, Veritas software company CEO, Vinod Khosla (Sun one of the founders of the company), Sun CEO of the Silicon Valley, composed of senior investment. There is no doubt that today db4objects hottest companies in Silicon Valley and one of the technological innovation.

Db4o Characteristics

Db4o objective is to provide a powerful, suitable for embedded database engine can work in the equipment, and mobile products, such as desktop and server platforms. Main features are as follows:

* The open-source model. And other ODBMS different db4o for open-source software, by the strength of the open source community-driven development db4o products.
* Original database. Db4o is 100% of the original object-oriented database programming language used to directly operate the database. OR mapping the need for programmers to store objects, saving programmers in the development of data storage time.
* High-performance. Figure 2 for the official announcement db4o benchmarking data, db4o than a Hibernate / MySQL test programme in some lines as much as 44 times higher than the speed! Installation is simple and only needs about 400Kb. Jar or. Dll library files. In the next series of articles, we will be only concerned with the application of the Java platform, but actually db4o will undoubtedly good. NET platform work.

Figure 2. Db4o official benchmark data
Open-source object-oriented database db4o trip: Acquaint db4o (Figure 2)

* ECO embedded. Db4o use only the introduction of more than 400 k jar files or dll file, minimal memory consumption.
* Zero management. Db4o without the use of DBA, zero management.
* Support for multiple platforms. Db4o Java support from 1.1 to Java 5.0, in addition to support. NET, CompactFramework, such as Mono. NET platform, but also can run in the CDC, PersonalProfile, Symbian, and the Zaurus Savaje reflection of that support J2ME dialect environment, but also in the running CLDC, MIDP, RIM / Blackberry, Palm OS does not support this reflection J2ME environment.

Perhaps developers will be asked if the existing application environment has been a relational database how do? It does not matter, the dRS db4o (db4o Replication System) can be realized db4o relational database with a two-way synchronization (reproduction), in Figure 3. DRS is based on Hibernate development, the current version is 1.0, and running on the Java platform version 1.2 or higher, can be realized based on dRS db4o to Hibernate / RDBMS, db4o to db4o and Hibernate / RDBMS to Hibernate / RDBMS two-way replication. DRS model in Figure 3

Figure 3. DRS model of open source object-oriented database db4o trip: Acquaint db4o (Figure 3)

Conclusion

Db4o because of its open-source philosophy, as well as the realization of innovation, access to the Java Pro 2006 Readers Choice Award. Whether or db4o from a successful case itself, this pure object-oriented databases are worthy of our attention, feedback from the official forum, a considerable users preparing to move to relational database db4o. And the latest release of version 5.5, has even more made many performance upgrade again. In the next article, I will continue to share with you db4o has brought us this object-oriented database turmoil.

About the author

Rosen Jiang from Chengdu, and OO db4o is the loyal fans, db4o is the 2005 winner of one of dvp. He is J2me applications using db4o, and you can contact him through rosener_722@hotmail.com.

Zhang Huang Zhu, love open-source software, and is familiar with Java / C / C + + programming language, database technology are interested in network technology. You can contact him through zhanghuangzhu@gmail.com.

Chris from Hong Kong, love and open source db4o. He founded the China's most fervent Java and the open-source community Matrix (http://www.Matrix.org.cn), and you can contact him through chris@Matrix.org.cn.