【Csdn.net 12月9日】Oracle数据库高昂的许可证费用和服务费一直以来为人诟
【Csdn.net 12月9日】Oracle数据库高昂的许可证费用和服务费一直以来为人诟病。2009年,全球深陷经济危机,就连美国总统奥巴马也不得不开源节流，因此被外界冠以开源总统之称。而就是在如此环境下，Oracle不仅仅没有下调价格，反而在今年7月，Oracle将其部分产品价格提高40%。涨价原因也没有得到任何形式的官方解释。这一切，都使得其核心用户忧心忡忡。基于以上原因，当前企业广泛使用oracle数据库的同时，不少企业也正在寻求可行的oracle替代方案。而开源数据库无疑是一个合适的替代方案。
MySQL前途未卜
MySQL、PostgreSQL、EnterpriseDB是全球三大开源数据库。MySQL被称为是最受欢迎的开源数据库，如今，它的前途因为Oracle与Sun并购而前途未卜。尽管Oracle承诺会保持MySQL的独立性，众多反对者还是担心，如果MySQL被最大的私有数据库厂商Oracle收归麾下，可能遭到Oracle的抛弃甚至打压。
EnterpriseDB异军突起 剑指Oracle
而作为PostgreSQL 衍生版本的EnterpriseDB却异军突起，近期频繁的市场动作无疑让人眼前一亮。11月23日，EnterpriseDB携手其大中国区独家总代理浦华众城在北京高调发布了Enterprise DB8.3版最新产品和多款解决方案。从其新闻稿中频繁出现挑战Oracle，如何撬动Oracle帝国的根基等词语我们不难看出其攻击性十足，目标非常明确直指Oracle。恰恰就在上个月的27日，Red Hat宣布以1900万美元注资Enterprise DB。值得注意的是去年3月，EnterpriseDB同样获得了一笔总额达1000万美元的投资，其中就有IBM的参与，并且IBM在DB2 9.7中嵌入了EnterpriseDB对Oracle数据库的兼容性，以此实现对Oracle数据库的兼容。
EnterpriseDB亚太区总经理邓恩说：EnterpriseDB进入中国的市场目标客户是争取原来Oracle数据库的客户，与MySQL不会在市场上产生直接的冲突。
浦华众城副总经理马越表示Oracle价格昂贵，EnterpriseDB在成本上无疑具有巨大优势。目前MYSQL正在走下坡路，而PostgreSQL则持续增长。从延展性的对比来看，PostgreSQL是优于MySQL的。
据悉将新的应用部署在与Oracle兼容的EnterpriseDB数据库中，较之Oracle，企业的IT支出将降低5倍。
PostgreSQL社区创始人之一、EnterpriseDB资深数据库架构师Bruce Momjian指出：EnterpriseDB提供企业级的开源数据库，但这并不是个很新的产品，是基于PostgreSQL，而PostgreSQL已经有20年的历史了。我们希望EnterpriseDB能占领数据库市场，这并非不可能，因为Linux就成功占领了服务器操作系统市场。
EnterpriseDB公司有两种版本的数据库，基本是从开源PostgreSQL数据库建立起来的。有网友戏称EnterpriseDB是山寨版的Oracle数据库。StandardServer是开源代码的硬件版本，这是类似于PostgreSQL的开放源代码，而AdvancedServer不是开源项目，而是与甲骨文数据库兼容的版本。
这个数据库究竟能山寨Oracle数据库到什么程度呢? 索尼在线娱乐公司(sony online entertainment)数据库技术服务总监David Manifold给出了答案。在将oracle迁移到EnterpriseDB数据库的过程中，80-90%的应用程序不需要经过任何修改即可直接运行。 David Manifold说。
EnterpriseDB企业版直接支持Oracle数据库的数据类型、SQL语法、PL/SQL、触发器、序列、自定义包及内建包等。针对Oracle设计的应用几乎不需修改即可在EnterpriseDB上运行。并且提供一键式迁移工具EnterpriseDB Migration Studio简化数据库迁移过程，并生成完整的迁移报告。
EnterpriseDB能够走多远?
挑战庞大的Oracle帝国需要勇气也需要实力，EnterpriseDB似乎已经具备这一基础，但Oracle在数据库市场的多年耕耘，其数据库市场的霸主地位EnterpriseDB要想轻易撬动Oracle帝国根基并不是太容易，另外开源数据库虽然具有相当的优势，但劣势也相当明显，MySQL如今前途未卜，EnterpriseDB又能够走多远呢?
关键词：EnterpriseDB 数据库
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