About

This project is a set of examples with inline explanations describing core topics of Spring Data JPA and Java Persistence API. If it was helpful, please leave a ⭐ 😊.

Contents and Project Structure

Project was divided into different packages focused on different aspects and topics of Spring Data JPA:

• entity - describes entity structure
• relationships - examples of entity relationships, relation ownership, presenting different approaches to model them
• inheritance - entity inheritance
• repository - focused on querying and modifying data
• cascading - all about different cascade approaches and their consequences in data modification
• fetching - different solutions to lazy and eager loading
• transaction - examples of transaction handling, levels of isolation, transaction propagation
• storedProcedures
• criteriaAPI
• locking

How to run this?

Although the real value in this project is code itself with its comments, you can run it using docker compose up in the project root directory and after the container has started by executing mvn package && java -cp target/spring-boot-data-jpa-1.0-SNAPSHOT.jar dev.k2.springbootdatajpademo.SpringBootDataJpaDemoApplication command.

If you'd like to use in memory database such as H2, simply replace postgres dependency for:

<dependency>
    <groupId>com.h2database</groupId>
    <artifactId>h2</artifactId>
</dependency>

in pom.xml and remove all spring.datasource.* properties from application.properties file. Then you can use mvn:asdad command to start the application.

Looking at table structure in Postgresql

If you'd like to look at table structure that was created in Postgres, recommended way is to use a tool such as Jetbrains' DataGrip.

However, if you don't have anything like that or don't want to do it the easy way, you can look directly in the docker container in these steps:

• Lookup your running postgres container id by running docker ps command
• Run docker -it ... to go into your container
• Once you're inside the container, run asd
• Now you can see all the tables