无法获取 Spring boot 以自动创建数据库模式

我无法让 Spring boot 在启动时自动加载数据库架构。

这是我的应用程序.属性：

spring.datasource.url=jdbc:mysql://localhost:3306/test
spring.datasource.username=test
spring.datasource.password=
spring.datasource.driverClassName = com.mysql.jdbc.Driver

spring.jpa.database = MYSQL

spring.jpa.show-sql = true

spring.jpa.hibernate.ddl-auto = create
spring.jpa.hibernate.dialect = org.hibernate.dialect.MySQL5Dialect
spring.jpa.hibernate.naming_strategy = org.hibernate.cfg.ImprovedNamingStrategy

这是我的应用程序.java：

@EnableAutoConfiguration
@ComponentScan
public class Application {
    public static void main(final String[] args){
        SpringApplication.run(Application.class, args);
    }
}

下面是一个示例实体：

@Entity
@Table(name = "survey")
public class Survey implements Serializable {

    private Long _id;

    private String _name;

    private List<Question> _questions;

    /**
     * @return survey's id.
     */
    @Id
    @GeneratedValue(strategy = IDENTITY)
    @Column(name = "survey_id", unique = true, nullable = false)
    public Long getId() {
        return _id;
    }

    /**
     * @return the survey name.
     */
    @Column(name = "name")
    public String getName() {
        return _name;
    }


    /**
     * @return a list of survey questions.
     */
    @OneToMany(mappedBy = "survey")
    @OrderBy("id")
    public List<Question> getQuestions() {
        return _questions;
    }

    /**
     * @param id the id to set to.
     */
    public void setId(Long id) {
        _id = id;
    }

    /**
     * @param name the name for the question.
     */
    public void setName(final String name) {
        _name = name;
    }

    /**
     * @param questions list of questions to set.
     */
    public void setQuestions(List<Question> questions) {
        _questions = questions;
    }
}

任何想法我做错了什么？