我想通过使用 Hibernate 创建一个 CRUD 存储库，将一些数据保存在 H2 数据库中。

我无法让数据库存储我的条目。目前，我正在尝试通过创建示例条目在更新数据库期间实现这一点。条目在日志中看起来不错，但未创建/更新/生成表。

为什么 Hibernate 在这种情况下不能创建表？(如果问题出在我的数据结构上)

这是我的实体，Game.java 类(我试过没有@Column 注释，没有区别。ID 不是自动生成的，我每次都需要能够输入自己的 ID) :

@Entity
@Table(name = "GAME")
public class Game {

    @Id
    @Column (name = "ID")
    private long id;

    @Column (name = "NAME")
    private String name;

    @Column(name = "STORYLINE", length = 4000)
    private String storyline;

    @Column(name = "AGGREGATED_RATING")
    @JsonProperty("aggregated_rating")
    private double aggregatedRating;

    @Column(name = "FIRST_RELEASE_DATE")
    @JsonProperty("first_release_date")
    private long firstReleaseDate;

    @Embedded
    private Cover cover;

    public Game(){

    }

    public Game(long id, String name, String storyline, double aggregatedRating, long firstReleaseDate, Cover cover) {
        this.id = id;
        this.name = name;
        this.storyline = storyline;
        this.aggregatedRating = aggregatedRating;
        this.firstReleaseDate = firstReleaseDate;
        this.cover = cover;
    }

    public long getId() {
        return id;
    }

    public String getName() {
        return name;
    }

    public String getStoryline() {
        return storyline;
    }

    public double getAggregatedRating() {
        return aggregatedRating;
    }

    public long getFirstReleaseDate() {
        return firstReleaseDate;
    }

    public Cover getCover() {
        return cover;
    }


}

这里是 Cover.java 类:

@Embeddable
public class Cover {

    @Column (name = "URL")
    private String url;
    @JsonProperty("cloudinary_id")
    @Column (name = "CLOUDINARY_ID")
    private String cloudinaryId;
    @Column (name = "WIDTH")
    private Integer width;
    @Column (name = "HEIGHT")
    private Integer height;

    public Cover(){
    }

    public Cover(String url, String cloudinaryId, Integer width, Integer height) {
        this.url = url;
        this.cloudinaryId = cloudinaryId;
        this.width = width;
        this.height = height;
}

    public String getUrl() {
        return url;
    }

    public String getCloudinaryId() {
        return cloudinaryId;
    }

    public Integer getWidth() {
        return width;
    }

    public Integer getHeight() {
        return height;
    }

}

我在这里配置了 H2 数据库，在 application.properties 文件中:

spring.h2.console.enabled=true
spring.h2.console.path=/h2_console
spring.datasource.url=jdbc:h2:mem:test;DB_CLOSE_DELAY=-1
spring.datasource.username=sa
spring.datasource.password=
spring.datasource.driverClassName=org.h2.Driver
spring.jpa.hibernate.ddl-auto = update
spring.jpa.show-sql=true
logging.level.org.hibernate.SQL=DEBUG
logging.level.org.hibernate.type.descriptor.sql.BasicBinder=TRACE

Repository 配置如下:

import org.springframework.data.repository.CrudRepository;

import java.util.List;

public interface GameRepository extends CrudRepository<Game, Long> {
    List<Game> findAllByName(String name);
}

我通过在 localhost:8080/test 下测试我的存储库，其中应将示例条目插入到表中:

@RequestMapping("/test")
public String saveSth(){
    gameRepository.save(new Game(127, "Assassin's Creed II", "The lineage continues as this new chapter introduces Ezio, inheritor of the talents and creed of the Assassins. His family murdered by rival families, Ezio resolves to learn the ancient art of the Assassin in order to seek revenge. He will not do so alone though, allying with historical figures such as philosopher and writer Niccolò Machiavelli. You will also be able to master the art of the assassin with all new weapons and instruments created by the renowned inventor and genius of the Renaissance, Leonardo Da Vinci himself.", 90.25, 1258416000000L, new Cover("//images.igdb.com/igdb/image/upload/t_thumb/doczeiofd1ckpapdhqs7.jpg", "doczeiofd1ckpapdhqs7", 1000, 1426)));
    return "success";
}

我得到以下日志:

2017-07-25 13:09:58.873 DEBUG 9442 --- [nio-8080-exec-1] org.hibernate.SQL                        : select game0_.id as id1_0_0_, game0_.aggregated_rating as aggregat2_0_0_, game0_.cloudinary_id as cloudina3_0_0_, game0_.height as height4_0_0_, game0_.url as url5_0_0_, game0_.width as width6_0_0_, game0_.first_release_date as first_re7_0_0_, game0_.name as name8_0_0_, game0_.storyline as storylin9_0_0_ from game game0_ where game0_.id=?
Hibernate: select game0_.id as id1_0_0_, game0_.aggregated_rating as aggregat2_0_0_, game0_.cloudinary_id as cloudina3_0_0_, game0_.height as height4_0_0_, game0_.url as url5_0_0_, game0_.width as width6_0_0_, game0_.first_release_date as first_re7_0_0_, game0_.name as name8_0_0_, game0_.storyline as storylin9_0_0_ from game game0_ where game0_.id=?
2017-07-25 13:09:58.875 TRACE 9442 --- [nio-8080-exec-1] o.h.type.descriptor.sql.BasicBinder      : binding parameter [1] as [BIGINT] - [127]
2017-07-25 13:09:58.894 DEBUG 9442 --- [nio-8080-exec-1] org.hibernate.SQL                        : insert into game (aggregated_rating, cloudinary_id, height, url, width, first_release_date, name, storyline, id) values (?, ?, ?, ?, ?, ?, ?, ?, ?)
Hibernate: insert into game (aggregated_rating, cloudinary_id, height, url, width, first_release_date, name, storyline, id) values (?, ?, ?, ?, ?, ?, ?, ?, ?)
2017-07-25 13:09:58.895 TRACE 9442 --- [nio-8080-exec-1] o.h.type.descriptor.sql.BasicBinder      : binding parameter [1] as [DOUBLE] - [90.25]
2017-07-25 13:09:58.896 TRACE 9442 --- [nio-8080-exec-1] o.h.type.descriptor.sql.BasicBinder      : binding parameter [2] as [VARCHAR] - [doczeiofd1ckpapdhqs7]
2017-07-25 13:09:58.896 TRACE 9442 --- [nio-8080-exec-1] o.h.type.descriptor.sql.BasicBinder      : binding parameter [3] as [INTEGER] - [1426]
2017-07-25 13:09:58.897 TRACE 9442 --- [nio-8080-exec-1] o.h.type.descriptor.sql.BasicBinder      : binding parameter [4] as [VARCHAR] - [//images.igdb.com/igdb/image/upload/t_thumb/doczeiofd1ckpapdhqs7.jpg]
2017-07-25 13:09:58.897 TRACE 9442 --- [nio-8080-exec-1] o.h.type.descriptor.sql.BasicBinder      : binding parameter [5] as [INTEGER] - [1000]
2017-07-25 13:09:58.897 TRACE 9442 --- [nio-8080-exec-1] o.h.type.descriptor.sql.BasicBinder      : binding parameter [6] as [BIGINT] - [1258416000000]
2017-07-25 13:09:58.897 TRACE 9442 --- [nio-8080-exec-1] o.h.type.descriptor.sql.BasicBinder      : binding parameter [7] as [VARCHAR] - [Assassin's Creed II]
2017-07-25 13:09:58.897 TRACE 9442 --- [nio-8080-exec-1] o.h.type.descriptor.sql.BasicBinder      : binding parameter [8] as [VARCHAR] - [The lineage continues as this new chapter introduces Ezio, inheritor of the talents and creed of the Assassins. His family murdered by rival families, Ezio resolves to learn the ancient art of the Assassin in order to seek revenge. He will not do so alone though, allying with historical figures such as philosopher and writer Niccolò Machiavelli. You will also be able to master the art of the assassin with all new weapons and instruments created by the renowned inventor and genius of the Renaissance, Leonardo Da Vinci himself.]
2017-07-25 13:09:58.897 TRACE 9442 --- [nio-8080-exec-1] o.h.type.descriptor.sql.BasicBinder      : binding parameter [9] as [BIGINT] - [127]

看起来数据已绑定(bind)到参数，但在 H2 控制台中 SELECT * FROM GAME 返回给我: 从游戏中选择 *； 未找到表“GAME”；语句: 从游戏中选择 * [42102-193] 42S02/42102(帮助)

我尝试过其他 H2 模式，例如 create-drop 或 create，但没有成功。让我担心的是，我什至无法让数据库创建一个包含正确行的空表，为条目做好准备。

我认为我的实体有问题或我的 GameRepository 配置丢失，但我没有更多的想法来修复此错误。

我想实现这里的目标: http://javasampleapproach.com/spring-framework/spring-boot/integrate-h2-database-springboot-spring-jpa-embedded-mode 和这里: http://www.simplecodestuffs.com/value-object-entity-object-in-hibernate-mapping/

此外，我尝试了这套教程进行更改: https://springframework.guru/using-the-h2-database-console-in-spring-boot-with-spring-security/ https://springframework.guru/spring-boot-web-application-part-3-spring-data-jpa/

但到目前为止还没有运气。

最佳答案

只需转到 H2 控制台，例如:http://localhost:9090/h2-console/ 在 JDBC URL 字段中，键入 jdbc:h2:mem:testdb 以配置与 RAM 中的 testdb 数据库的连接。

关于java - H2 未在我的 Spring Boot 应用程序中创建/更新表。我的实体有问题吗？，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/45302132/