About JPA

41-50 of 200Refresh
Manual
99

Locking in JPA

JPA 2 supports both optimistic locking and pessimistic locking. Locking is essential to avoid ... in ObjectDB (and in JPA) is always at the database object level, i.e. each database object is locked ... some ORM JPA providers) is defined in the entity class or not. Pessimistic Locking The main
Manual
99

JPA Named Queries

can be defined in JPA XML mapping files instead of using the @NamedQuery annotation. ObjectDB supports JPA XML ... mainly for Object Relational Mapping (ORM) JPA providers and less so when using ObjectDB ... ("SELECT c FROM Country c"); List results = query.getResultList(); One of the reasons that JPA requires
Tutorial
99

Getting Started with JPA [2011-02-09]

This tutorial demonstrates how to create and run a simple JPA application. The demonstrated application uses JPA to store and retrieve simple Point entity objects, where each Point has two persistent fields - x and y. If you already know JPA - the source code will be straightforward
JPA Doc
98

JPA Queries

Queries are represented in JPA by the Query and TypedQuery interfaces: The JPA Query API section (in chapter 4 of the ObjectDB manual) provides detailed explanation of how exactly to use ... concatenating JPQL strings into a valid complete JPQL query. JPA 2 introduced the JPA Criteria Query API, as
Manual
98

Database Connection using JPA

Working with the Java Persistence API (JPA) consists of using the following interfaces: Overview ... for Query instances, which are needed for executing queries on the database. Every JPA implementation ... of ObjectDB classes that implement these interfaces, and because standard JPA interfaces are used
Manual
98

Retrieving JPA Entity Objects

The Java Persistence API (JPA) provides various ways to retrieve objects from the database ... that has already been fetched from the database is available in objects that are detached. JPA 2 introduces methods ... queries. The official query language of JPA is JPQL (Java Persistence Query Language). It enables
Manual
98

Updating JPA Entity Objects

classes are in use. It is usually recommended to use collections rather than arrays when using JPA. Collections are more portable to ORM JPA implementations and provide better automatic change tracking ... have to be modified in one operation. The UPDATE Queries in JPA/JPQL in chapter 4 explains how to use JPA UPDATE queries.
Manual
98

Chapter 4 - JPA Queries (JPQL / Criteria) [2011-04-01]

The JPA Query Language (JPQL) can be considered as an object oriented version of SQL. Users ... well as how to use the JPA Criteria API, which provides an alternative way for building queries in JPA, based on JPQL. The first section describes the API that JPA provides for using dynamic and static
Manual
98

Chapter 4 - JPA Queries (JPQL / Criteria) [2018-09-15]

The JPA Query Language (JPQL) can be considered as an object oriented version of SQL. Users ... well as how to use the JPA Criteria API, which provides an alternative way for building queries in JPA, based on JPQL. The first section describes the API that JPA provides for using dynamic and static
Manual
98

Chapter 4 - JPA Queries (JPQL / Criteria)

The JPA Query Language (JPQL) can be considered as an object oriented version of SQL. Users ... well as how to use the JPA Criteria API, which provides an alternative way for building queries in JPA, based on JPQL. The first section describes the API that JPA provides for using dynamic and static