org.springframework.dao.InvalidDataAccessResourceUsageException：无法提取结果集；

Question

类实体

@Entity
    @Table
    public class Camera {
        @Id
        @GeneratedValue(strategy = GenerationType.AUTO)
        private Long id;
        private String name;
        private String place;
        private String address;
public Long getId() {
        return id;
    }

    public String getName() {
        return name;
    }

    public String getPlace() {
        return place;
    }

    public void setId(Long id) {
        this.id = id;
    }

   //Constructors, getters and setters are not shown here

    }

application.properties 配置文件

spring.datasource.url= jdbc:mysql://localhost:3306/springbootdb
spring.datasource.username=root
spring.datasource.password=
server.port=9000

我有这个错误

enter image description here

    Exception in thread "Thread-3" org.springframework.dao.InvalidDataAccessResourceUsageException: could not extract ResultSet; SQL [n/a]; nested exception is org.hibernate.exception.SQLGrammarException: could not extract ResultSet
Caused by: org.hibernate.exception.SQLGrammarException: could not extract ResultSet
    Caused by: org.hibernate.exception.SQLGrammarException: could not extract ResultSet
Caused by: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: La table 'springbootdb.camera' n'existe pas

我必须在数据库中手动创建表才能工作:(知道吗？是配置文件有问题吗？谢谢你的帮助:)

Answer 1

在您的 application.properties 文件中添加以下属性：

spring.jpa.hibernate.ddl-auto=update

这将初始化您的数据库。根据 spring 文档查看其他属性：

https://docs.spring.io/spring-boot/docs/current/reference/html/howto-database-initialization.html