Book Image

Mastering Hibernate

By : Ramin Rad, Koushik Srinivas Kothagal
Book Image

Mastering Hibernate

By: Ramin Rad, Koushik Srinivas Kothagal

Overview of this book

Hibernate has been so successful since its inception that it even influenced the Java Enterprise Edition specification in that the Java Persistence API was dramatically changed to do it the Hibernate way. Hibernate is the tool that solves the complex problem of Object Relational Mapping. It can be used in both Java Enterprise applications as well as .Net applications. Additionally, it can be used for both SQL and NoSQL data stores. Some developers learn the basics of Hibernate and hit the ground quickly. But when demands go beyond the basics, they take a reactive approach instead of learning the fundamentals and core concepts. However, the secret to success for any good developer is knowing and understanding the tools at your disposal. It’s time to learn about your tool to use it better This book first explores the internals of Hibernate by discussing what occurs inside a Hibernate session and how Entities are managed. Then, we cover core topics such as mapping, querying, caching, and we demonstrate how to use a wide range of very useful annotations. Additionally, you will learn how to create event listeners or interceptors utilizing the improved architecture in the latest version of Hibernate.
Table of Contents (16 chapters)

Native SQL


Native SQL statements are also supported in Hibernate, except you will need to use a different API call to compose a query object. There are mainly two reasons you would want to use a native SQL. The first is that you wish to use a specific feature offered by your database solution that may not be supported by Hibernate. The second is when you wish to execute an ad hoc query and store the result in an object that is not a Hibernate entity.

If you don't associate an entity with the query result, Hibernate returns the result set in a list of object array. This is known as a Scalar Query. However, you can associate an entity with the native query and Hibernate will return a list of this entity; this is known as Entity query. Let's see how these work.

Scalar query

When you execute a native SQL, the result of this query is returned in a list of object arrays. Consider the following query:

List<Object[]> objectList = session
.createSQLQuery("SELECT * FROM PERSON")
  .list();

Each element...