 18 | 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 |
18 | 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 |
17 | 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 |
17 | 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 |
17 | to connect to the master server in order to listen to updates. The updates are automatically applied ... 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 |
17 | cannot include 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 |
17 | 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 |
16 | 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 |
16 | 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 |
16 | () {
TypedQuery 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 |