無法使用 Spring 引導在 MySQL 數據庫中自動創建表

Question

我是 Spring Boot 的新手，並嘗試從 MySQL 數據庫中的實體創建表，但不幸的是，在運行我的應用程序后什么都沒有創建。 這是我的代碼：

用戶.java

@Entity
public class User {
    @Id
    @GeneratedValue
    private Long id;

    private String firstName;

    private String lastName;

    @Column(unique = true, nullable = false)
    private String username;

    @Column(nullable = false)
    private String password;

    private String prevPass;

    @Column(nullable = false)
    private Organization organization;

    @ManyToMany
    @Column(nullable = false)
    private Set<Role> roles = new HashSet<>();

    @Column(nullable = false)
    private Boolean enabled = true;

    @Column(nullable = false, unique = true)
    private String email;

    private String position;

    public User() {
    }
}

角色.java

@Entity
public class Role {
    @Id
    @GeneratedValue
    private Long id;

    @Column(unique = true, nullable = false)
    private String code;

    @Column(unique = true, nullable = false)
    private String title;
}

應用程序屬性

spring.datasource.url= jdbc:mysql://localhost:3306/test
spring.datasource.username=root
spring.datasource.password=sth
spring.jpa.hibernate.ddl-auto=update

pom.xml 依賴項

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.3.2.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

    <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>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-tomcat</artifactId>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
            <exclusions>
                <exclusion>
                    <groupId>org.junit.vintage</groupId>
                    <artifactId>junit-vintage-engine</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
    </dependencies>

我也用過

spring.jpa.hibernate.ddl-auto=create

and 

spring.jpa.hibernate.ddl-auto=create-drop

在我的 application.properties 文件中。 我不得不提一下，我的實體與包含@SpringBootApplication注釋的 class 位於同一個 package 中。 這是日志：

2020-08-10 22:52:14.139  INFO 10011 --- [           main] a.b.c.abc          : Starting abc on user with PID 10011 
2020-08-10 22:52:14.139  INFO 10011 --- [           main] a.b.c.abc          : No active profile set, falling back to default profiles: default
2020-08-10 22:52:15.339  INFO 10011 --- [           main] .s.d.r.c.RepositoryConfigurationDelegate : Bootstrapping Spring Data JPA repositories in DEFERRED mode.
2020-08-10 22:52:15.370  INFO 10011 --- [           main] .s.d.r.c.RepositoryConfigurationDelegate : Finished Spring Data repository scanning in 23ms. Found 0 JPA repository interfaces.
2020-08-10 22:52:16.292  INFO 10011 --- [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat initialized with port(s): 8080 (http)
2020-08-10 22:52:16.307  INFO 10011 --- [           main] o.apache.catalina.core.StandardService   : Starting service [Tomcat]
2020-08-10 22:52:16.307  INFO 10011 --- [           main] org.apache.catalina.core.StandardEngine  : Starting Servlet engine: [Apache Tomcat/9.0.37]
2020-08-10 22:52:16.495  INFO 10011 --- [           main] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring embedded WebApplicationContext
2020-08-10 22:52:16.495  INFO 10011 --- [           main] w.s.c.ServletWebServerApplicationContext : Root WebApplicationContext: initialization completed in 2180 ms
2020-08-10 22:52:16.886  INFO 10011 --- [           main] o.s.s.concurrent.ThreadPoolTaskExecutor  : Initializing ExecutorService 'applicationTaskExecutor'
2020-08-10 22:52:16.948  INFO 10011 --- [         task-1] o.hibernate.jpa.internal.util.LogHelper  : HHH000204: Processing PersistenceUnitInfo [name: default]
2020-08-10 22:52:17.011  WARN 10011 --- [           main] JpaBaseConfiguration$JpaWebConfiguration : spring.jpa.open-in-view is enabled by default. Therefore, database queries may be performed during view rendering. Explicitly configure spring.jpa.open-in-view to disable this warning
2020-08-10 22:52:17.042  INFO 10011 --- [         task-1] org.hibernate.Version                    : HHH000412: Hibernate ORM core version 5.4.18.Final
2020-08-10 22:52:17.378  INFO 10011 --- [         task-1] o.hibernate.annotations.common.Version   : HCANN000001: Hibernate Commons Annotations {5.1.0.Final}
2020-08-10 22:52:17.724  INFO 10011 --- [         task-1] com.zaxxer.hikari.HikariDataSource       : HikariPool-1 - Starting...
2020-08-10 22:52:18.251  INFO 10011 --- [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat started on port(s): 8080 (http) with context path ''
2020-08-10 22:52:18.258  INFO 10011 --- [           main] DeferredRepositoryInitializationListener : Triggering deferred initialization of Spring Data repositories…
2020-08-10 22:52:18.259  INFO 10011 --- [           main] DeferredRepositoryInitializationListener : Spring Data repositories initialized!
2020-08-10 22:52:18.299  INFO 10011 --- [           main] a.b.c.abc          : Started abc in 4.794 seconds (JVM running for 9.263)
2020-08-10 22:52:18.786  INFO 10011 --- [         task-1] com.zaxxer.hikari.HikariDataSource       : HikariPool-1 - Start completed.
2020-08-10 22:52:18.817  INFO 10011 --- [         task-1] org.hibernate.dialect.Dialect            : HHH000400: Using dialect: org.hibernate.dialect.MySQL8Dialect

任何人都可以幫助我嗎？

Answer 1

執行以下操作可能會有所幫助：

1. 運行 class 應該有@SpringBootApplication或者至少一個配置類應該有@EnableAutoConfiguration 。
2. 您不需要 tomcat 作為依賴項。
3. 您能否更新您的 pom 文件以向我們展示 Spring 引導父級？

Answer 2

我終於解決了。 無法創建表，因為我沒有為外鍵使用一對一關系。