Problem creating table in H2 database with SpringBoot

Question

My greetings for respectful users I'm newbie with spring boot and i want just create simple table in H2 database this is the model class

@Entity
public class Human 

{

    @Id
    private long id;


    private String firstname;

    private String lastname;

        private String email;

        public long getId() {
            return id;
        }




        public void setId(int id) {
            this.id = id;
        }
        public String getFirstname() {
            return firstname;
        }
        public void setFirstname(String firstname) {
            this.firstname = firstname;
        }
        public String getLastname() {
            return lastname;
        }
        public void setLastname(String lastname) {
            this.lastname = lastname;
        }
        public String getEmail() {
            return email;
        }
        public void setEmail(String email) {
            this.email = email;
        }
}

and this is pom.xml:

<?xml version="1.0" encoding="UTF-8"?>
<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>2.1.9.RELEASE</version>
    <relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.example</groupId>
<artifactId>demo-1</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>demo-1</name>
<description>Demo project for Spring Boot</description>

<properties>
    <java.version>1.8</java.version>
</properties>

<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-data-jpa</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>

    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-devtools</artifactId>
        <scope>runtime</scope>
        <optional>true</optional>
    </dependency>
    <dependency>
        <groupId>com.h2database</groupId>
        <artifactId>h2</artifactId>
        <scope>runtime</scope>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-test</artifactId>
        <scope>test</scope>
    </dependency>
</dependencies>

<build>
    <plugins>
        <plugin>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-maven-plugin</artifactId>
        </plugin>
    </plugins>
</build>

and application.properties:

spring.h2.console.enabled= true
spring.h2.console.path=/h2
spring.datasource.url=jdbc:h2:file:~/user
spring.datasource.username=sa
spring.datasource.password=
spring.datasource.driver-class-name=org.h2.Driver

until here the app works well, the only problem that the table doesn't show in H2 console (I don't know if it's really created or not but when I use H2 console the table was created instantly)

So please what's the problem could be? Any help is appreciated

Answer 1

There are a couple of things that you need to check and verify to ensure this works.

• Make sure to define the repository layer correctly.Also ensure you have provided all the correct annotations.
• If you have create queries for the tables make sure that you put these queries in a file name schema.sql .Also, ensure that the file is put under the directory src/main/resources/ folder.But when providing the schema.sql make sure to disable the spring.jpa.hibernate.ddl-auto as both won't work at the same time as intented.

In a JPA-based app, you can choose to let Hibernate create the schema or use schema.sql, but you cannot do both. Make sure to disable spring.jpa.hibernate.ddl-auto if you use schema.sql.

• If you have any data updation queries to be executed put them inside a file names data.sql .Also, ensure that the file is put under the directory src/main/resources/ folder.This will be executed after the ddl-auto creates the tables.

Repository layer like:

@Repository
public interface HumanRepository extends JpaRepository<Human, Integer> {

}

As @sovannarith cheav said you need to provide the property in application.properties or application.yml like:

spring.jpa.hibernate.ddl-auto=update
spring.jpa.generate-ddl=true
spring.jpa.database-platform=org.hibernate.dialect.H2Dialect

The spring.jpa.hibernate.ddl-auto property can have different values depending upon your use-case.Values for this property can be:

validate: validate the schema, makes no changes to the database.
update: update the schema.
create: creates the schema, destroying previous data.
create-drop: drop the schema at the end of the session.

If this didn't work perhaps springboot is not identifying H2, so try setting the following:

spring.datasource.platform=h2
spring.datasource.initialization-mode=always

Official Doc

Answer 2

The solution here is just adding annotation for main class

@EntityScan("com.example.model")

So here Spring will scan the package com.example.model and connet with H2 database then create the table

The table human of origins Human entity