14 | Running JPA Queries (with getResultList) The following query retrieves all the Country objects in the database. The query ... that to only print the country names, a query using projection and retrieving country names directly instead of retrieving the entire Country instances would be more efficient. Single Result Query |
14 | JPA Exceptions to retrieve entity objects from the database. For example, when a required entity object is not found: or during query execution: The lock exceptions (above) may also be thrown during retrieval, if database lock has been requested for retrieved entity objects and it cannot be granted. |
11 | Setting and Tuning of JPA Queries for the first page), the following expression retrieves the results for a specified page: List<Country ... that has to be applied on all the result objects that the query retrieves. For example, the following query |
11 | Query Parameters in JPAQuery parameters enable the definition of reusable queries. Such queries can be executed with different parameter values to retrieve different results. Running the same query multiple times ... ) The following method retrieves a Country object from the database by its name: public Country |
2 | Step 3: Add a Main Class to store Point objects in the database and then retrieve them from the database. Use copy and paste ... : " + q2.getSingleResult()); // Retrieve all the Point objects from the database ... in the database, and then run a few queries, including a query that retrieves all the 1000 Point |
2 | Step 4: Add a Servlet Class: The EntityManagerFactory is retrieved from the application scope attribute, and then an EntityManager ... the database. All the Guest entity objects are retrieved from the database and stored in the request's |
2 | Step 3: Define an EJB Session Bean); } // Retrieves all the guests: public List<Guest> getAllGuests ... - for retrieving all the existing Guest objects from the database. EJB classes are only supported by Java EE |
2 | Step 3: Define a Spring DAO Component); } // Retrieves all the guests: public List<Guest> getAllGuests() { TypedQuery<Guest> query ... - for storing a new Guest entity object in the database. getAllGuests - for retrieving all the existing |
2 | Step 3: Define a Spring DAO Component public void persist(Guest guest) { em.persist(guest); } // Retrieves ... Guest entity object in the database. getAllGuests - for retrieving all the existing Guest objects |
1 | [ODB1] Chapter 5 - JDO Connections storing, retrieving, updating and deleting database objects, are provided in the next chapter (Chapter ... instances) at the same time. In an active transaction, on every retrieval of an object from ... , object retrieval, reading) can be done without an active transaction. The default in ObjectDB |
