Hibernate maven dependency

<dependency> <groupId>org.hibernate</groupId> <artifactId>hibernate-core</artifactId> <version>5.4.16.Final</version> </dependency><dependency> <groupId>org.hibernate</groupId> <artifactId>hibernate-core</artifactId> <version>5.4.16.Final</version> </dependency>

Eclipse maven hibernate project

Eclipse maven hibernate project: Eclipse provides m2eclipse plugin to integrate Maven and Eclipse together. Steps to create maven java project in eclipse: In eclipse, click on File menu → New → Maven Project. Select maven-archetype-quickstart template to create java project and Click on Next button. Now provide the group Id, artifact Id and Package. Click … Read more

merge vs update Hibernate

Update and Merge both work on detached instances, ie instances which have a corresponding entry in the database but which are currently not attached to a Session. Both methods are used to convert these object into persistence state from detached state. The update tries to reattach the instance, that means that there may be no … Read more

save vs update vs saveorupdate Hibernate

Save: Save Serializable save(Object object) throws HibernateException   Serializable save(String entityName, Object object) throws HibernateExceptionSerializable save(Object object) throws HibernateException Serializable save(String entityName, Object object) throws HibernateException Save method is used to store an object into the database. It insert an entry if the identifier doesn’t exist. It will throw error if the identifier already exist. … Read more

save vs persist Hibernate

Save(): 1. Syntax: public Serializable save(Object object) throws HibernateException. 2. The return type of the save method is java.io.Serializable. It returns the generated Id after saving the record. 3. It can save the changes to the database outside of the transaction. i.e. Save method can be used inside or outside the transaction. 4. Session.save() for … Read more

openSession vs getCurrentSession Hibernate

The SessionFactory.getCurrentSession() returns a session bound to a context. We don’t need to close this. We have to set hibernate.current_session_context_class to thread and then implement something like a servlet filter that opens the session. We can access that session anywhere else by using the SessionFactory.getCurrentSession(). thread The SessionFactory.openSession() always opens a new session that we … Read more

get() vs load() Hibernate

session.load() • It will always return a “proxy” in Hibernate terms without hitting the database. In Hibernate, proxy represents a fake object with the given identifier value but its properties are not initialized yet. • If no record found, it will throws an ObjectNotFoundException. • Example: Let we call session.load(Employee.class,new Integer(10)). Hibernate will create one … Read more

Hibernate transaction management

Transaction: A transaction is a sequence of operation which works as an atomic unit. A transaction only completes if all the operations completed successfully. A transaction has the Atomicity, Consistency, Isolation and Durability properties (ACID). Transaction interface: Transaction interface provides the facility to define the units of work or transactions. A transaction is associated with … Read more

Hibernate native SQL

Native SQL refers to the real SQL for used database. Hibernate provides the facility to use native SQL. We can create a native SQL by createSQLQuery() method of Session interface. Syntax of Hibernate native SQL which returns an object array: Query query = session.createSQLQuery(“nativeSQL”); Syntax of Hibernate native SQL which returns an entity: Query query = … Read more

Hibernate named query using annotation

Named query is a concept of using queries by name. First a query is defined and a name is assigned to it. Then it can be used anywhere by this alias name. Syntax of hibernate named query using annotation: @NamedQueries({ @NamedQuery(name = " queryName ", query = " queryString ") })@NamedQueries({ @NamedQuery(name = " queryName … Read more