OneToMany 由多的一方维护关系 既(Many方)
public class Huitie implements Serializable {
@OneToMany
@JoinColumn(name = "huifutie_id", referencedColumnName = "id", insertable = false, updatable = false)
private List<Pinglunren> pinglunrens;
}
只在一方映射,另外一方不写的时候
维护关系方 添加 注解 @JoinColumn(name = "user_id", referencedColumnName = "id")
name 属性 为多的一方(Pinglunren) 的外键在数据库里面的名字 ,referencedColumnName 为映射另一方(Huitie )的主键 id
如果出现
public class Huitie implements Serializable {
@Column(name = "user_id")
private Long userId;
@OneToOne(fetch = FetchType.EAGER)
@JoinColumn(name = "user_id", referencedColumnName = "id", insertable = false, updatable = false)
private User user;
}
映射字段一样的,需要添加 insertable = false, updatable = false,否则会不知道应该是映射属性 还是 对象
OneToOne 由自己维护关系
name 属性 为自己(Huitie)在数据库里面的外键名字 referencedColumnName 为User 的主键id
@OneToMany
@JoinColumn(name = "publish_pay_id", referencedColumnName = "id", insertable = false, updatable = false)
private List<PublishBuy> publishBuys1;
映射后,查询时,可以通过 .any() 设置映射后,可以设置查询集合的条件,
注意如果映射集合的条件不满足,那么当前对象和对象里面映射的集合对象都不会返回
QPublishPay qPublishPay = QPublishPay.publishPay;
List<PublishPay> publishPays = jpaQueryFactory
.selectFrom(qPublishPay)
.where(qPublishPay.userid.eq(userId)
.and(qPublishPay.publishBuys1.any().status.eq("2")))
.fetch();
return ServiceResponse.createBySuccess(publishPays);