我收到错误“列“systementi0_.Id 不存在”。我正在使用 PostgreSql 和 Hibernate。 有我的实体的代码:
@Entity
@Table(name = "system_table", schema = "blue_schema")
public class SystemEntity {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Column(name = "Id", unique = true)
private int id;
@Column(name = "name")
private String name;
@Column(name = "sys_description")
private String systemDescription;
@Column(name = "tech_description")
private String technologyDescritpion;
@Column(name = "owner_name")
private String owner;
public SystemEntity() {
// TODO Auto-generated constructor stub
}
public SystemEntity(int id, String name, String systemDescription, String technologyDescritpion, String owner) {
super();
this.id = id;
this.name = name;
this.systemDescription = systemDescription;
this.technologyDescritpion = technologyDescritpion;
this.owner = owner;
}
public SystemEntity(String name, String systemDescription, String technologyDescritpion, String owner) {
super();
this.name = name;
this.systemDescription = systemDescription;
this.technologyDescritpion = technologyDescritpion;
this.owner = owner;
}
一开始,我试图从数据库中获取该表中的所有数据。
@Override
public List<SystemEntity> getAllSystems() {
Session currentSession = sessionFactory.getCurrentSession();
Query<SystemEntity> theQuery = currentSession.createQuery("from SystemEntity", SystemEntity.class);
List<SystemEntity> listOfSystems = theQuery.getResultList();
return listOfSystems;
}
这是我的数据库类型和输出: Table output
我的模式名称在@Table注释中得到了澄清,但仍然出现错误:
SEVERE: Servlet.service() for servlet [dispatcher] in context with path [/ContractManager] threw exception [Request processing failed; nested exception is javax.persistence.PersistenceException: org.hibernate.exception.SQLGrammarException: could not extract ResultSet] with root cause
org.postgresql.util.PSQLException: Error: columnsystementi0_.id does not exist.
我看到了与我类似的帖子,但解决方案很简单,只需在 @Table 中添加架构名称即可。
最佳答案
这是一个常见的错误。第一个建议:不要在所有数据库实体的名称中使用大写字母:模式、表或列。
您的 id
列名称包含“Id”。尝试“id”。
第二:我推荐你在postresql中使用序列生成器:
@Entity
@Table(name = "system_table", schema = "blue_schema")
@SequenceGenerator(schema = "blue_schema", name = "system_table_seq", allocationSize = 1, sequenceName = "system_table_seq")
public class SystemEntity {
// other code below
// ...
}
最后的建议:不要在 JPA 实体中使用原始类型。 尝试:
@Entity
@Table(name = "system_table", schema = "blue_schema")
@SequenceGenerator(schema = "blue_schema", name = "system_table_seq", allocationSize = 1, sequenceName = "system_table_seq")
public class SystemEntity {
@Id
@GeneratedValue(generator = "system_table_seq", strategy = GenerationType.SEQUENCE)
private Integer id;
// other code below
// ...
}
关于java - org.postgresql.util.PSQLException : Error: column systementi0_. id 不存在 - Hibernate、PostgreSql,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/58477715/