Spring Data JPA: Implementing OneToMany Association

Learn one-to-many associations it’s and implementation

Introduction

• In this article, we will learn about the one-to-many association, when to use them, and implement them using Spring data JPA using one example.

One to Many Association

• Let's understand the one-to-many association with a simple example. We have two entities/tables in the database. One is Customer and another is CreditCard.
• A Customer can have one or more CreditCard which defines the relationship between one to many.
• One-to-many relationships exist in the database when one row in the table has a relation with many rows in another table.

Entities

• Let’s define the necessary entities for our use case.

Customer

• In the customer entity, we need to define the @OneToMany relation where we define the List of CreditCard as a child association.
• This association will basically allow us access to all the CreditCard belonging to a given Customer entity.

@Entity
@Table(name="customer")
public class Customer {
    @Id
    @GeneratedValue(strategy=…