Java DB is Sun's supported distribution of the open source Apache Derby database. Its ease of use, standards compliance, full feature set, and small footprint make it the ideal database for Java developers. Java DB is written in the Java programming language, providing "write once, run anywhere" portability. It can be embedded in Java applications, requiring zero administration by the developer or user. It can also be used in client server mode. Java DB is fully transactional and provides a standard SQL interface as well as a JDBC 4.0 compliant driver.
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The Java Data Objects (JDO) API is a standard interface-based Java model abstraction of persistence. Application programmers can use JDO technology to directly store Java domain model instances into the persistent store (database). Benefits include ease of programming, application portability, database independence, high performance, and optional integration with Enterprise JavaBeans (EJB). JDO has been developed under Java Specification Request 12 ( JSR 12) and Java Specification Request 243 ( JSR 243). Beginning with JDO 2.0, the development of the API and the Technology Compatibility Kit (TCK) takes place within the Apache JDO open-source project.
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The Java Database Connectivity (JDBC) API is the industry standard for database-independent connectivity between the Java programming language and a wide range of databases SQL databases and other tabular data sources, such as spreadsheets or flat files. The JDBC API provides a call-level API for SQL-based database access.
JDBC technology allows you to use the Java programming language to exploit "Write Once, Run Anywhere" capabilities for applications that require access to enterprise data. With a JDBC technology-enabled driver, you can connect all corporate data even in a heterogeneous environment.