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EclipseLink/FAQ
This is the EclipseLink FAQ, please feel free to post "common" questions here about EclipseLink that you believe "other" users we find "useful". Please do not use this to ask general questions or for issues you are having using the product or for support, please post these types of questions to the EclipseLink Forum.
Please add your questions to the most suitable category or create a new category. (to add a question edit this page and provide a link to your question).
General
These are general frequently asked questions focused on what the Eclipse Persistence Services (EclipseLink) project is, what the various persistence services are as well as general questions about the project.
Complete list of general questions and their answers
- What is the Eclipse Persistence Services Project (EclipseLink)?
- How is EclipseLink Licensed?
- What are the components of EclipseLink?
- Where can I download EclipseLink?
- How do I get started using EclipseLink?
- Can I use EclipseLink with Maven?
- What is the relationship between EclipseLink and the Oracle TopLink product?
EclipseLink's Caching
EclipseLink's object-caching is one of its most powerful and unique features. The caching applies to users of EclipseLink's JPA (and Native ORM), DBWS, and EIS. These frequently asked questions focus on how EclipseLink's entity cache works and how it is most commonly used and configured.
- How to disable the shared cache?
- How to refresh the shared cache?
- How can caching be used in a application server cluster?
See "Understanding Caching" in the Understanding EclipseLink (concepts guide) and "Enhancing Performance" in the EclipseLink Solutions Guide, both available in the EclipseLink Documentation Center, for additional information.
EclipseLink JPA, ORM
- What is Object-Relational Persistence: JPA?
- What version of JPA does EclipseLink support?
- What features beyond JPA does EclipseLink support?
- What are the best practices for using EclipseLink JPA?
- Migrating to EclipseLink JPA
- What databases are supported?
- Does EclipseLink support NoSQL databases?
- How is EclipseLink integrated with the Oracle database?
- How to access table, column and schema information at runtime?
- How to access the JDBC connection?
- How to enable logging?
- How to disable or enable weaving?
- How to generate tables and DDL?
- Are stored procedures and triggers supported?
- How to get the SQL for a Query?
- How to diagnose and resolve hangs and deadlocks?
- Do I have to maintain both sides of a bi-directional relationship?
- How to access what changed in an object or transaction?
- How to avoid trimming the trailing spaces on a CHAR field?
See the EclipseLink JPA Extensions Guide in the EclipseLink Documentation Center for more information.