java - Hibernate 不自动创建表

Question

pom.xml:

<dependencies>
    ...
    <dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-orm</artifactId>
    <version>4.2.2.RELEASE</version>
</dependency>
    <dependency>
        <groupId>org.hibernate</groupId>
        <artifactId>hibernate-entitymanager</artifactId>
        <version>5.0.3.Final</version>
    </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.springframework.boot</groupId>
        <artifactId>spring-boot-starter-test</artifactId>
        <scope>test</scope>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-thymeleaf</artifactId>
    </dependency>
</dependencies>

实体:

@Entity
@Table(name = "person")
public class Person {

@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private int personId;

@Column(name = "first_name")
private String firstName;
}

application.properties

spring.datasource.url=jdbc:mysql://localhost:3306/socialmedia? 
allowPublicKeyRetrieval=true&useSSL=false
spring.datasource.username=username
spring.datasource.password=password
spring.datasource.driver.class=com.mysql.cj.jdbc.Driver
spring.jpa.database-platform=org.hibernate.dialect.MySQL5InnoDBDialect
spring.jpa.properties.hibernate.default_schema = socialmedia
spring.jpa.hibernate.ddl-auto = create-drop
spring.jpa.show-sql = true

Hibernate 不会自动创建表，我已经设置了属性和实体类，并且依赖项在运行代码后架构仍然为空。没有显示错误消息。

Answer 1

你的策略是:

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

这意味着 Hibernate 创建表，并在程序运行后删除表。这就是为什么您看不到任何表格的原因。

您必须使用create(仅创建表)或update(也更改表):

 spring.jpa.hibernate.ddl-auto = update

然后我在您的 pom.xml 中没有看到 JPA 启动项目，但您有不必要的 Hibernate 依赖项。您的 pom.xml 应该如下所示:

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

    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <scope>runtime</scope>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-test</artifactId>
        <scope>test</scope>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-thymeleaf</artifactId>
    </dependency>
</dependencies>

spring-boot-starter-data-jpa 将自动配置 Hibernate。