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EclipseLink/DesignDocs/356812
Design Specification: Database Change Event Cache Invalidation
Document History
Date | Author | Version Description & Notes |
---|---|---|
2011-09-06 | James | 0.1 Draft |
Project overview
Some databases support raising change events when tables are updated or changed. It is also possible in some databases to raise events from triggers, and some third party products support raising database change events.
When a share cache is used in EclipseLink it can become stale if other applications (or other nodes) update the database directly.
This project will provide an infrastructure for supporting database change events to invalidate the changed objects in the EclipseLink shared cache.
Oracle's Database Change event Notification will be supported for Oracle databases.
Concepts
Oracle DCN : The Oracle database Database Change event Notification feature available since Oracle 10.2.
Requirements
- Support generic database change event listener.
- Support Oracle DCN
- Support cache invalidation of change objects.
Design Constraints
- Must support database events with limited information, such as only the table ROWID.
Functionality
Testing
Add a JPA test model for DCN testing to the Oracle tests. Test:
- multiple tables (with versioning)
- inheritance
- relationships (with versioning)
- ensure objects invalidated in other session
- test native SQL queries
- test update-all queries
API
- @Cache(
Native API
- DatabaseEventNotificationListener (org.eclipse.persistence.platform.database.events)
- OracleDCNListener (org.eclipse.persistence.platform.oracle.dcn)
Config files
- orm.xml
<cache-index> <column name="F_NAME"/> <column name="L_NAME"/> </cache-index>
Documentation
Should be documented under caching section.
Open Issues
Issue # | Owner | Description / Notes |
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1 | ||
2 |
Decisions
Issue | Description / Notes | Decision |
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