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A lot of ENT and SIV instances which are not cleared by GC

through mapped by to-many relationships. Please check the new build. If you still get the exception we may need a test case that demonstrate the issue in order to explore it further. support Support

Paths and Types in JPQL and Criteria API

classes) are represented in JPQL by the following types of expressions: Variables - FROM ... and functions (e.g. for strings and for numbers), they can be compared by all six comparison operators, and they can be used in ordering. Navigation through Path Expressions A path expression always starts

FROM clause (JPQL / Criteria API)

at the WHERE clause level by using a type expression. For example, in the following query, c iterates ... , and the same query can also be written as follows: SELECT c FROM Country c By default, the name ... name). The default name can be overridden by specifying another name explicitly in the @Entity's

Shared (L2) Entity Cache

an entity object that is already managed by the EntityManager returns the existing instance from ... by the EntityManagerFactory and shared by all its EntityManager objects. the broader scope ... is wider, since they exist per database and are shared by all the EntityManagerFactory and EntityManager


have been specified. Returns: having clause predicate Since: JPA 2.0 List<Order> getOrderList() Return the ordering expressions in order of precedence. Return the ordering expressions in order of precedence. Returns empty list if no ordering expressions have been specified. Modifications to the list

Database Replication and Clustering

to connect to the master server in order to listen to updates. The updates are automatically ... can manage different types of databases, including master databases, slave database (by using one or ... The configuration above demonstrates a situation in which the master database is managed by a server

JPA Queries

three groups. SELECT and ORDER BY elements (including tuples): FROM clause elements (representing range ... Queries are represented in JPA by the Query and TypedQuery interfaces: The JPA Query API section ... only at runtime (e.g. depending on which fields are filled by a user in a form) can be done by

CRUD Database Operations with JPA

the results (using an ORDER BY clause) and even group results (using GROUP BY and HAVING clauses). JPQL ... a managed entity) by the persist method. The new Point objects are physically stored in the database ... objects in the database by using a simple query: Query q1 = em.createQuery("SELECT COUNT(p) FROM


multiple variables and JOIN, and cannot include the GROUP BY, HAVING and ORDER BY clauses ... As explained in chapter 2, entity objects can be deleted from the database by: Retrieving ... transaction, either explicitly by calling the remove method or implicitly by a cascading operation


queries cannot include the GROUP BY, HAVING and ORDER BY clauses, but the WHERE clause ... Existing entity objects can be updated, as explained in chapter 2, by: Retrieving the entity ... . Applying changes to the database by calling the commit method. JPQL UPDATE queries provide

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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