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:: Spring Boot :: (v2.7.13)
问题描述:
使用JPA编辑实体时报错:
not-null property references a null or transient value : com.psquare.book.entity.system.Role.createAt; nested exception is org.hibernate.PropertyValueException: not-null property references a null or transient value : com.psquare.book.entity.system.Role.createAt
解决方法:
报错的字段恰好时更新时不需要的字段,在字段对应的@Column注解中设置updatable=false解决
@Column(nullable = false, updatable = false) private Date createAt; @Column(nullable = false, length = 50, updatable = false) private String createBy;
也可以先使用ID获取当前需要更新的实体,然后修改需要更新的字段后再使用save保存,这样每次更新都是全字段,如果字段比较多对数据库性能会有影响。可以在实体类上使用@DynamicUpdate注解,这样hibernate在生成更新SQL时就只包含值有变更并且不为null的字段。 但这样如果在当前事务中没有获取过当前实体,Hibernate会先查询下数据库,以便获取到实体进行字段对比。
未使用@DynamicUpdate注解生成的更新SQL edit:test_hot3
Hibernate: select role0_.id as id1_1_0_, role0_.create_at as create_a2_1_0_, role0_.create_by as create_b3_1_0_, role0_.update_at as update_a4_1_0_, role0_.update_by as update_b5_1_0_, role0_.description as descript6_1_0_, role0_.name as name7_1_0_ from role role0_ where role0_.id=?
Hibernate: update role set update_at=?, update_by=?, description=?, name=? where id=?
添加@DynamicUpdate
@DynamicUpdate public class Role
使用了@DynamicUpdate注解后生成的更新SQL edit:test_hot4
Hibernate: select role0_.id as id1_1_0_, role0_.create_at as create_a2_1_0_, role0_.create_by as create_b3_1_0_, role0_.update_at as update_a4_1_0_, role0_.update_by as update_b5_1_0_, role0_.description as descript6_1_0_, role0_.name as name7_1_0_ from role role0_ where role0_.id=?
Hibernate: update role set update_at=?, name=? where id=?
使用了@DynamicUpdate注解后,在service中先load再更新 生成的SQL edit:test_hot5Hibernate: update role set update_at=?, name=? where id=?