H2 Database Engine with testing

Bonjour ! tout le monde

Today i will write about H2 Database testing with spring boot and the problem that i had faced with my current project.

What is H2 Database? →H2 database is Java SQL database which a embedded server modes and in-memory databases.

The main features of H2 Database according to https://www.h2database.com/html/main.html

• Very fast, open source, JDBC API
• Embedded and server modes; in-memory databases
• Browser based Console application
• Small footprint: around 2 MB jar file size

For my project , we are using Spring boot and Spring Data JPA.

I will show you the structure

A java project

A pom.xml

The pom.xml of my project

We will try to use H2 database to be two type databases. Frist is a Postgres database with Hibernate (OR Mapping) and second is oracle with JDBC template. But during the implementation, we cannot initial the JDBC bean.

The first version of configuration

application-test.yml

I have got errors 1.org.springframework.boot.autoconfigure.jdbc.DataSourceInitializerInvoker 2.org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name.

After that, we try to reseach about the problem to use the H2 databases with multiple database and multiple way to initail ( JPA Hibernate and JDBC template to connect at the same times).

The Last version of configuration

we decided to workaroud with this case by using one database with 2 schemas. You can see the configuration below:

application-test.yml (last version)

data-h2.sql

schema-h2.sql

Moreover, i will show you the configuration with Spring boot (Java)

TestConfiguration class

Testing class

From above photo , the Repository is a class that extend CrudRepository

For the information (References):

https://www.baeldung.com/spring-boot-hibernate https://www.springboottutorial.com/hibernate-jpa-tutorial-with-spring-boot-starter-jpa https://howtodoinjava.com/spring-boot2/datasource-configuration/ https://www.mkyong.com/spring-boot/spring-boot-jdbc-examples/