Introduction In this article, we are going to see how you can change the @OneToOne shared primary key column name when using JPA and Hibernate. This has been a recurrent theme when answering questions about Hibernate or during my High-Performance Java Persistence training. As previously explained, the one-to-one database table relationship requires the Primary Key to be shared among the parent and the child tables. Unfortunately, just adding the JPA @OneToOne annotation in the child entity does not render a true one-to-one table relationship since a separate Foreign Key column will be… Read More
Introduction In this article, I’m going to show you the best way to map a ManyToMany association when using JPA and Hibernate. As simple as JPA annotations might be, it’s not always obvious how efficient they are behind the scenes.
Introduction While adding a @OneToMany relationship is very easy with JPA and Hibernate, knowing the right way to map such an association so that it generates very efficient SQL statements is definitely not a trivial thing to do. In a relational database system, a one-to-many association links two tables based on a Foreign Key column so that the child table record references the Primary Key of the parent table row. As straightforward as it might be in a relational database, when it comes to JPA, the one-to-many database association can be represented… Read More