HQL (Hibernate Query Language) - Insert Query Example

This post shows how to perform an insert query using HQL in Hibernate application.

Hibernate Query Language (HQL) is an object-oriented query language, similar to SQL, but instead of operating on tables and columns, HQL works with persistent objects and their properties. HQL queries are translated by Hibernate into conventional SQL queries, which in turn perform an action on a database.

HQL Insert Query Syntex

The BNF for an HQL INSERT statement is:

insert_statement ::=
    insert_clause select_statement

insert_clause ::=
    INSERT INTO entity_name (attribute_list)

attribute_list ::=
    state_field[, state_field ]*

HQL Insert Query Example

public void insertStudent() {
        Transaction transaction = null;
        try (Session session = HibernateUtil.getSessionFactory().openSession()) {
            // start a transaction
            transaction = session.beginTransaction();

            String hql = "INSERT INTO Student (firstName, lastName, email) " +
                "SELECT firstName, lastName, email FROM Student";
            Query query = session.createQuery(hql);
            int result = query.executeUpdate();
            System.out.println("Rows affected: " + result);

            // commit transaction
            transaction.commit();
        } catch (Exception e) {
            if (transaction != null) {
                transaction.rollback();
            }
            e.printStackTrace();
        }
    }

Learn hibernate at https://www.javaguides.net/p/hibernate-tutorial.html.

Reference

https://www.javaguides.net/2018/11/hibernate-query-language-insert-update.html