About JOIN


Database File Compression

ObjectDB database files are usually smaller than database files of other Database Management Systems (object and Relational) but still, an additional internal compression is possible. Usually smaller files are also faster because less I/O operations are required and memory cache can be used more efficiently. But compression and decompression consumes CPU time. Therefore, the effect of compression on Object databases is currently unknown. Feature Request Version: Priority: Normal Status: Active Replies: 0 Type:  Feature Request ...


JDOQL Subqueries (JDO 2.1)

Subqueries (or nested queries) have been added to the JDOQL (JDO Query Language) in version 2.1 of JDO. This is currently the main feature that of JDO 2.0-2.1-2.2 that is still missing in ObjectDB 2. JDO Feature Version: Priority: Low Status: Active Replies: 0 Type:  JDO Feature ...


Embedded Database Replication

As we all know, embedded databases out perform server databases on every occasion. The problem with embedded databases is that theyre difficult to scale. If I were to create an entire enterprise web application within a single jar file using embedded tomcat and embedded objectdb I would run into problems trying to cluster the data. It would be really useful if some kind of new external replicator application was created that can be used by server administrators to ensure replication is optimal and healthy. Feature Request Version: 2.6.1 Priority: Normal Status: Active Replies: 0 Type:  Feature Request ...



Return the metamodel representation for the set attribute.(Method of javax.persistence.criteria.SetJoin)


Email notification about new build

Just a quick thought. It would be nice to get email notification about new builds. If a new build resolves a problem that I'm not subscribed for, I don't know about it until i check ODB page :) Website Version: 2.4.4 Priority: Normal Status: Active Replies: 0 Type:  Website ...



(Optional) The foreign key columns of the join table which reference the primary table of the entity owning the association.(Annotation Element of javax.persistence.JoinTable)



Generate or assume a foreign key constraint exists on the column or columns associated with this join.(Annotation Element of javax.jdo.annotations.Join)



(Required) The map key join columns that are used to map to the entity that is the map key.(Annotation Element of javax.persistence.MapKeyJoinColumns)



(Optional) The columns that are used to join with the primary table.(Annotation Element of javax.persistence.SecondaryTable)


Explorer Features - refresh + viewing open embedded database

Request for feature: Ability to auto-refresh an explorer view, say at regular intervals of a few seconds. (at a minimum one ought to be able to manually refresh, for example the list of persistent types). additionally, it would be useful to be able to view an embedded database (read only mode) via the explorer. Feature Request Version: 2.2.2 Priority: High Status: Active Replies: 0 Type:  Feature Request ...