EXist: Check out this open source database management system that USES XQuery.

eXist：查看这个使用Xquery的开源数据库管理系统。

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Apache CouchDB is an open source document-oriented database management system that stores data as JSON objects.

Apache CouchDB是一个基于开源文档的数据库管理系统，它将数据存储为JSON对象。

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The eXist native XML database: Experiment with XQuery with this open source database management system entirely built on XML technology.

eXist 本地 XML 数据库：体验 XQuery 与这种完全构建于 XML 技术之上的开源数据库管理系统。

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Over time, cost pressure has led the IT organizations to consider open source for mission critical components such as database management systems (mySQL) or the operating system itself (Linux).

FORBES: Four Questions (And Answers) About Open Source Software In Finance