Mckoi SQL Database is an Open Source SQL Database System written in Java. Mckoi SQL Database was started in 1998, and the goal was to build a database management system in a traditional shared disk/shared memory style architecture.
Apache Lucene 是一個高效能,全功能,跨平台的文字搜尋引擎函式庫,完全以Java寫成,適用於全文搜尋方面各面向的應用需求。Lucene 原本由 Doug Cutting 在1999年寫成,其後在2001年加入Apache Software Foundation,並於2005年成為 Apache Software Foundation轄下的重要專案之一。現在該專案包含的元件除了Apache Lucene Core之外,還有以Apache Lucene Core為基礎的 Apache Solr 搜尋伺服器。由於Web 2.0的網路共工模式興起,全球的使用者日積月累地在網路上製造了大量的資料,而如何搜尋、處理這些相關資料,也就成為了資料探勘方面重要的技術,並且在應用面,也可以與各資料儲存網站配合,搭建出新興的資訊服務文創產業。Apache Lucene提供資訊搜索與彙整方面的解決方案,所以現階段已被許多具有龐大資料庫的知名網站採用,例如Twitter、LinkedIn;並且在學術研究方面,亦不乏採用Apache Lucene做為資料探勘研究平台的專案。就如同Apache Software Foundation其他專案一般,Apache Lucene以Apache License 2.0授權釋出,任何人皆可任意使用,並以此作為基礎續行開發。
C-JDBC is an open source (LGPL) database cluster middleware that allows any Java application (standalone application, servlet or EJB container, ...) to transparently access a cluster of databases through JDBC(tm). The database is distributed and replicated among several nodes and C-JDBC balances the queries among these nodes. C-JDBC handles node failures and provides support for checkpointing and hot recovery.
DB is a Project of the Apache Software Foundation, charged with the creation and maintenance of commercial-quality, open-source, database solutions based on software licensed to the Foundation, for distribution at no charge to the public.
Apache ObJectRelationalBridge (OJB) is an Object/Relational mapping tool that allows transparent persistence for Java Objects against relational databases.
Apache Torque is an object-relational mapper for java. In other words, Torque lets you access and manipulate data in a relational database using java objects. Unlike most other object-relational mappers, Torque does not use reflection to access user-provided classes, but it generates the necessary classes (including the Data Objects) from an XML schema describing the database layout (which can either be written by hand or generated from an existing database). The XML schema can also be used to generate and execute a SQL script which creates all the tables in the database.
Speedo is an open source implementation of the JDO (TM) 1.0.1 specification.