7 | Setting and Tuning of JPA Queries on which they were invoked). Flush Mode (setFlushMode) Changes made to a database using an EntityManager ... . Therefore, before a query is executed, uncommitted database changes (if any) have to be flushed to the database in ... ); Flushing changes to the database before every query execution affects performance significantly |
7 | WHERE clause (JPQL / Criteria API) JPQL query that retrieves selective objects from the database. Out of the four optional clauses ... over all the Country objects in the database using the c range variable. Before passing these Country ... with millions of objects in the database there is a huge difference in query execution time if proper |
7 | What is ObjectDB?ObjectDB is an Object Oriented Database Management System (ODBMS). It provides all the standard database management services (storage and retrieval, transactions, lock management, query processing ... objects (and graphs of objects) in an ObjectDB database directly. There's no need to define tables or |
7 | ObjectDB 2.8 Developer's GuideWelcome to ObjectDB for Java/JPA Developer's Guide. Here you can learn how to develop database ... the following six chapters: Demonstrates basic database programming using ObjectDB and JPA. Shows ... , retrieve, update and delete database objects. Explains how to use the JPA Query Language (JPQL). Presents |
1 | Step 3: Add a Context Listener ClassThe Guest entity objects will be stored in an ObjectDB database, which will be represented by ... a ServletContextListener to perform initialization and cleanup operations: The database will be opened (or created ... . The database will be closed when the web application stops (or when the web server shuts down), by |
1 | Step 2: Entity Class and Persistence UnitTo store objects in an ObjectDB database using JPA we need to define an entity class: Open the [New ... the [Provider and Database] step just click Finish to generate a default persistence.xml file ... in the database was created in the project (under Source Packages > guest). Use copy and paste |
1 | Step 2: Entity Class and Persistence UnitTo store objects in an ObjectDB database using JPA we need to define an entity class: Right click ... that should represent Guest objects in the database was created in the project (under Java Resources ... guests in the database. We also need to configure JPA by setting a META-INF/persistence.xml file |
1 | Step 2: Entity Class and Persistence UnitTo store objects in an ObjectDB database using JPA we need to define an entity class: Open the [New ... the [Provider and Database] step click Finish to generate a default persistence.xml file ... the database was created in the project (under Source Packages > guest). Use copy and paste to replace |
1 | Step 2: Define a JPA Entity ClassTo store objects in an ObjectDB database using JPA we need to define an entity class: Open the [New ... to create the new class. The new class should represent Guest objects in the database. Use copy ... + ")"; } } The new class should represent Guest objects in the database. Besides the @Entity |
1 | Step 3: Add a Context Listener ClassThe Guest entity objects will be stored in an ObjectDB database, which will be represented by ... a ServletContextListener to perform initialization and cleanup operations: The database will be opened (or created ... . The database will be closed when the web application stops (or when the web server shuts down), by |
