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An instance of this class is thrown when attempting to create an object id when the object id constructor parameter is null.(Exception of JDO)


[ODB1] Chapter 5 - JDO Connections

The PersistenShows how to use database connections and transactions in JDO. ceManagerFactory interface represents a factory of database connections. Its main role is to provide PersistenceManager instances. The PersistenceManager interface represents a database connection. Every operation on a database requires a PersistenceManager instance. The Transaction interface represents a transaction on a database. Every operation that modifies the content of the database requires an active transaction.[toc hidden:1]... instance represents a specific database address (local or remote), and connections to that database are obtained using its ... using embedded mode, specify either its absolute path or its relative path. The JDOHelper.getPersistenceManagerFactory( ...


Entity Management Settings

Explains settings and performance tuning of JPA entities in ObjectDB, the fast Java object database for JPA/JDO.... The agent attribute (whose value is "true" or "false" ) specifies whether the Enhancer Agent should be loaded to ... This is currently supported only for JDK 6.0 (not JRE) or above. The reflection attribute specifies how non enhanced ...


Locking in JPA

Explains how to use optimistic locking and pessimistic locking in JPA.... commit. Any database object that has to be updated or deleted is checked. An exception is thrown if it is found out that an update ... checks every database object that has to be updated or deleted, and compares the version number of that object in the database to ...



Type of criteria query parameter expressions.(Interface of JPA)


Delete me

Is there a way to encrypt the odb file so that if hackers somehow steal it they cannot access the data without some kind of password? I would imagine accessing the database from java could just have another connection parameter while accessing from explorer.jar/exe would need to prompt the user for a password for encrypted odb files. ... systems support encryption of complete drives, directories or files, and an ObjectDB database is an ordinary file. If you are ... a Java file from a class file and see the password, or run the application on another computer), but it may be better than ...


[ObjectDB 2.5.5_03] Unexpected exception (Error 990)

Hello! When I run this query SELECT t FROM Unit t WHERE t.lastGeocodedPosition IS NULL OR t.lastGeocodedPosition.receiveTime < :lastGeocodedPosition.receiveTime I get the following exception: ... t WHERE t . lastGeocodedPosition IS NULL OR t . lastGeocodedPosition . receiveTime < ... t WHERE t . lastGeocodedPosition IS NULL OR t . lastGeocodedPosition . receiveTime < :receiveTime ...


FROM clause (JPQL / Criteria API)

Explains how to use the FROM clause and JOIN expressions in a JPA/JPQL query.... MAX, MEMBER, MIN, MOD, NEW, NOT, NULL, NULLIF, OBJECT, OF, OR, ORDER, OUTER, POSITION, SELECT, SET, SIZE, SOME, SQRT, SUBSTRING, SUM, ... JPA interface A join to an entity, embeddable, or basic type. See JavaDoc Reference Page... interface (and its sub ...



... You should start by following a  tutorial or reading the manual . For upgrading from version 1.0 please read ... 2.3.3 Improved compilation performance of OR queries with many elements. Fixed eager fetch of maps and ...


Object DB vs EclipseLink/TopLink: Unloaded relationships in detached entities

This topic is for those considering migrating from EclipseLink JPA or TopLink to ObjectDB JPA. ... is for those considering migrating from EclipseLink JPA or TopLink to ObjectDB JPA. This concerns a huge "gotcha" that other ... I was convinced that this involved either an ObjectDB bug or departure from the JPA spec by ObjectDB, but thanks to insistence and ...