When it comes to accessing relational databases with Java, people usually think of two options: 1. SQL (Structured Query Language) 2. ORM (Object Relational Mapping) Because the usage of SQL ...
Introduction to Database Migrations with Spring Boot and Flyway
If you are working with Spring Boot there are several ways to initialize the database. You could create a schema.sql, add it to the classpath and ...
How to JOIN two Entities without Mapped Relationship
Often you don’t want to map all relationships in an entity model (a blog post about this topic in detail will follow). Let’s have a look at this class diagram: There is no mapping between ...
Inheritance in JPA
Relational databases have tables and columns and object-oriented programming languages have classes and fields but they also provide inheritance. A concept that is not known in relational ...
Should you use Enums with JPA?
With JPA it’s possible to map Java enums to columns in a database table using the Enumerated annotation: An enum can be mapped as an integer or a string but mapping of enums that contain state ...
