About database

manual

ObjectDB Developer's Guide

... Developer's Guide. Here you can learn how to develop database applications using ObjectDB and JPA (Java Persistence API). The main ... Chapter 1 - Quick Tour Demonstrates basic database programming using ObjectDB and JPA. Chapter 2 - JPA ...

 
manual

JPA Entity Fields

Explains how to define and use primary keys in JPA, including composite and embedded primary keys.... in persistence and their values are never stored in the database (similar to transient fields in Java that do not participate in ... entity fields with no real content to be stored in the database. Persistent Fields Every non-static non-final entity ...

 
manual

Updating JPA Entity Objects

Explains how to use JPA to delete (remove) entity objects from the database.... Modifying existing entity objects that are stored in the database is based on transparent persistence, which means that changes are ... Update Once an entity object is retrieved from the database (no matter which way) it can simply be modified in memory from inside ...

 
release

2.3.3

... fields with cascading persist after updating the database and before commit (issue #78 ). Fixed ... JPQL queries. Added support of ";drop" database url parameter. Adjusted the Enhancer to the new Java 7 ... exceptions. Improved support of non standard database file suffixes. Changed fetch of collection elements. ...

 
manual

JPA Primary Key

Explains how to define and use primary keys in JPA, including composite and embedded primary keys. Every entity object that is stored in the database has a primary key. Once assigned, the primary key cannot be modified. ... represents the entity object as long as it exists in the database. As an object database, ObjectDB supports implicit object IDs, ...

 
page

Which API should I use - JPA or JDO?

... with relational databases. ObjectDB is the only object database that supports JPA. On the other hand, JDO is designated to be used ...

 
forum_thread

Doctor - high memory usage

Hi, Is it possible to reduce Doctor memory usage? Right now for recovering 67MB database, I need to set heap space to at least 450MB. Even then whole process takes ages. Optimal setting for this database is about 650MB. It's about ten times of size of database. ... reduce Doctor memory usage? Right now for recovering 67MB database, I need to set heap space to at least 450MB. Even then whole process takes ages. Optimal setting for this database is about 650MB. It's about ten times of size of database. ...

 
page

What is the Java Persistence API (JPA)?

... to represent persistent data can significantly simplify database programming. A JPA implementation (sometimes referred to as a JPA provider) is needed in order to interact with a relational database such as Oracle, DB2, SQL Server or MySQL. The popular JPA ...

 
faq

Is ObjectDB scalable? What are its limitation?

... applications. ObjectDB supports: Database file size up to 128 TB (= 131,072 GB = 134,217,728 MB). Up to 2,147,483,648 entity classes per database file. Up to 2,147,483,648 indexes per database file. ...

 
release

2.7.2

... in the Explorer. Fixed a bug in reusing database space after removing an index. Improved error message on ... Added an option for possibly improved concurrent database file access. Added automatic logging of query details on ...