About join

issue

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 ...

 
issue

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 ...

 
api-jpa

getModel()

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

 
forum_thread

adding tutorial videos to youtube

Hello , it will be good for you to add video tutorials for objectdb and explorer on youtube. #1 2013-02-02 22:45 Hello , it will be good for you to add video tutorials for objectdb and explorer on youtube. ...

 
issue

Support for roles/groups in ObjectDB

ObjectDB should incorporate roles/group in ObjectDB config file? I see no support for this. I would like to place several users under a given group or role, but I see no way of doing this as no such element is present  in the config file. Maybe under the $default, or any particular user, there could be a role/group element which would categorise the user further. This would help in authentication.   Thanks Feature Request Version: 2.3.3 Priority: Normal Status: Active Replies: 0 Type:  Feature Request ...

 
issue

New Java 8 (JDK 1.8) Collection Methods

ObjectDB version 2.5.5 (and above) supports Java 8 (JDK 1.8). Tracking changes to collections and maps using some new Java 8 methods is currently not fully supported. The main known issue is that orphan removal does not happen as a result of removing a reference to an object (which becomes an orphan) using the new methods: removeIf(predicate) and remove(key, value). Feature Request Version: 2.5.5 Priority: Normal Status: Active Replies: 0 Type:  Feature Request ...

 
api-jpa

JoinTable.joinColumns

(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)

 
api-jdo

Join.generateForeignKey

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

 
api-jpa

MapKeyJoinColumns.value

(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)

 
issue

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 ...