10 | UPDATE SET Queries in JPA/JPQL 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 |
10 | DELETE Queries in JPA/JPQL 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 |
10 | Obtaining a JPA Database ConnectionIn JPA a database connection is represented by the EntityManager interface. Therefore, in order ... to get an EntityManager instance. JPA requires the definition of a persistence unit in an XML file in order ... is considered by ObjectDB to be a database URL rather than a persistence unit name. The $objectdb |
10 | JPA Query Expressions (JPQL / Criteria) consists of clauses - SELECT, FROM, WHERE, GROUP BY, HAVING and ORDER BY, and each clause consists ... of at least one atomic component. More complex query expressions are built by combining atomic ... the following operators (in order of decreasing precedence): Navigation operator (.) Arithmetic operators |
2 | Step 3: Define an EJB Session Bean() { TypedQuery<Guest> query = em.createQuery( "SELECT g FROM Guest g ORDER BY g.id", Guest ... Operations on the database will be performed by an instance of a session bean (EJB) class that we will define in this step: Open the [New Session Bean] dialog box by right clicking the guest package |
2 | Step 3: Define an EJB Session Bean ORDER BY g.id", Guest.class); return query.getResultList(); } } The GuestDao session ... Operations on the database will be performed by an instance of a session bean (EJB) class that we will define in this step: Open the [New Java Class] dialog box by right clicking the guest package |
1 | [ODB1] Chapter 1 - About ObjectDB ObjectDB is compliant with the JDO (Java Data Objects) standard, developed by Sun ... and Microsoft SQL Server. In addition, by using JDO you are backed up by a large community that's expanding ... database concepts and the tables and columns defined for an application in order to perform the necessary |
1 | ObjectDB 1.0 Manual technology by Sun Microsystems. The main purpose of this guide is to familiarise you with ObjectDB ... class is and which types are supported by JDO. Chapter 4 - JDO Metadata Shows how to define JDO metadata ... (SQL, JDBC or JDO) is not required in order to follow this guide, but a strong background |
1 | javax.jdo.JDOEntityManager by the server. Get the Date as seen by the server. Clients using this method can order ... to the type specified by the resultClass argument. Parameters: name - the name of a query defined in ... item, which must be assignable to the type specified by the resultClass argument. Parameters: qlString |
0 | javax.jdo.PersistenceManager the PersistenceManagerFactory (recommended) or by construction. Since: JDO 1.0 void ... JDOUserException if the instance is transient or is managed by another PersistenceManager. Parameters: pc ... the affected instances is as specified by the FetchPlan. Parameters: pc - the instance to detach Returns |
