Spring Boot Error With Multiple datasources (Access to DialectResolutionInfo cannot be null)

I am a starter, and I created a simple web service app by refering this tutorial: https://spring.io/guides/gs/accessing-data-mysql/

And then I tried to do some modifications for accesing the second database and I got an error for that.
I checked my database and its users, and they seem okay.

Can anyone help me with it? Thanks!

java.lang.IllegalStateException: Failed to load ApplicationContext
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'userRepository' defined in TableReady.WebService.Repositories.UserRepository defined in @EnableJpaRepositories declared on JpaRepositoriesRegistrar.EnableJpaRepositoriesConfiguration: Cannot resolve reference to bean 'jpaMappingContext' while setting bean property 'mappingContext'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'jpaMappingContext': Invocation of init method failed; nested exception is org.hibernate.service.spi.ServiceException: Unable to create requested service [org.hibernate.engine.jdbc.env.spi.JdbcEnvironment]
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'jpaMappingContext': Invocation of init method failed; nested exception is org.hibernate.service.spi.ServiceException: Unable to create requested service [org.hibernate.engine.jdbc.env.spi.JdbcEnvironment]
Caused by: org.hibernate.service.spi.ServiceException: Unable to create requested service [org.hibernate.engine.jdbc.env.spi.JdbcEnvironment]
Caused by: org.hibernate.HibernateException: Access to DialectResolutionInfo cannot be null when 'hibernate.dialect' not set

enter image description here

application.properties

spring.jpa.hibernate.ddl-auto=update

spring.datasource1.url=jdbc:mysql://${MYSQL_HOST:localhost}:3306/users
spring.datasource1.username=user_info_admin
spring.datasource1.password=(@.SjFHn8LqdL)7/

spring.datasource2.url=jdbc:mysql://${MYSQL_HOST:localhost}:3306/general
spring.datasource2.username=general_admin
spring.datasource2.password=sP7Y86.=-k<hKSgG

JpaConfig.java

@Configuration
public class JpaConfig {
    @Bean
    @Primary
    @ConfigurationProperties(prefix="spring.datasource1")
    public DataSource primaryDataSource() {
        return DataSourceBuilder.create().build();
    }

    @Bean
    @ConfigurationProperties(prefix="spring.datasource2")
    public DataSource secondaryDataSource() {
        return DataSourceBuilder.create().build();
    }
}

MainController.java

@Controller // This means that this class is a Controller
@RequestMapping(path = "/users") // This means URL's start with /demo (after Application path)
public class MainController {

    // This means to get the bean called userRepository
    // Which is auto-generated by Spring, we will use it to handle the data
    @Autowired
    private UserRepository userRepository;

    @Autowired
    private RestaurantRepository restaurantRepository;

    // something else...
    // ...
    // ...
}

Restaurant.java

@Entity
@Table(name = "restaurants", schema = "general")
public class Restaurant {
    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Integer id;

    private String name;
    private String address;
    private String email;
    private String phone;
    // ...
    // ...
}

User.java

@Entity
@Table(name = "users", schema = "users")
public class User {
    @Id
    @GeneratedValue(strategy=GenerationType.AUTO)
    private Integer id;
    private String password;
    private String name;
    private String email;
    private String phone;
    // ...
    // ...
}

Both repos look like:

public interface SomeRepository extends CrudRepository<User, Integer> {
}

This issue could be caused by the database server being down or not accessible. Please check if the database server is running.

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