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160

persisting object with long[][] arrays of array

Hi, I have an object I am trying to persist (java) - It has several fields of type long[][]. It is taking very long to persist and sometimes never finish - it hangs on getTransaction().commit ... static final long serialVersionUID = 1L;     public @Id String id;     @OneToMany(fetch
143

Lazy loading does not work - crud takes long

.**.Datapoint,com.**.Advalm);         long t0 = System.currentTimeMillis();         projects = service ... , generator = "PROJECT_SEQUENCE")     private Long id;     ..     ..     @OneToMany(cascade
143

Schema migration - long to String

Hi, I need to change field type in our model from long to String. After changing filed type in our model and repairing database with doctor, most of our entities is gone. Doctor puts some errors ... ? lwalkowski Lukasz Walkowski Changing a field from long to String should not require any specific action
142

First persist takes long time

" /> Could you explain the long time for first persist? btc_es BTC EmbeddedSystems Some operations
142

Explorer shows Long id, but should be Integer

Hi! I have seen a strange behavior of ObjectDB Explorer: it shows @Id as being Long, not Integer as it's normally declared in the java class. This happens now with all entities in all 3 databases used for one project. If I open one of the entities in the explorer, then I click on it's id (in
142

EntityManager.refresh takes a long time

EntityManager.refresh takes a long time for entity object Person in this code:     logger.log(Level.INFO, "begin select for person " + new Date().toString());                TypedQuery<Person> personQuery =         em.createQuery("SELECT m FROM Person m", Person.class);     List<Person
51

Database Schema Evolution

to any numeric type. In this context numeric types are: byte, short, char, int, long, float, double, Byte, Short, Character, Integer, Long, Float, Double, BigInteger, BigDecimal and enum values ... long as the elements are convertible (e.g. from int[] to ArrayList<Long>). From any object to any
45

JPA Persistable Types

: boolean, byte, short, char, int, long, float and double. Equivalent wrapper classes from package java.lang: Boolean, Byte, Short, Character, Integer, Long, Float and Double. java.math.BigInteger ... ) collection and map types are supported, as long as their values (i.e. elements in collections and arrays
21

JPA Primary Key

key cannot be modified. It represents the entity object as long as it exists in the database. As ... 64 bit number (long) that is set automatically by ObjectDB for every new entity object ... key field: @Entity public class Project { @Id @GeneratedValue long id; // still set
20

JPA Metamodel API

ID attribute - including inherited: SingularAttribute<MyEntity,Long> id1 = entityType.getId(Long.class); // Gets a single ID attribute - excluding inherited: SingularAttribute<MyEntity,Long> id2 =   entityType.getDeclaredId(Long.class); // Checks if the type has a version

Getting Started

ObjectDB is very easy to use. Follow the Getting Started Tutorial and the Quick Tour manual chapter and in minutes you may be able to write and run first Java programs against ObjectDB.

Prior knowledge or experience in database programming (SQL, JDBC, ORM, JPA, etc.) is not required, but some background in using the Java language is essential.

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