Hibernate throws - 无法删除或更新父行：外键约束失败答案

【问题标题】：Hibernate throws - Cannot delete or update a parent row: a foreign key constraint failsHibernate throws - 无法删除或更新父行：外键约束失败
【发布时间】：2017-06-12 22:17:28
【问题描述】：

我正在执行一项基本任务以删除级联任务，但我遇到了异常。

Missions 类与ResponsesCheckLists 类具有OneToMany 关系，OneToMany 与StatistisquesMissions 类具有OneToMany 关系。

我有以下实体：

Missions.java

@Entity
public class Missions implements Serializable{

@Id
@GeneratedValue(strategy=GenerationType.IDENTITY)
@Column(name="idMission")
private long idMission;

@Column(name="nomMission")
private String nomMission;

@OneToMany(mappedBy="Respmission", cascade=CascadeType.ALL, fetch=FetchType.LAZY)
private Collection <ResponsesCheckLists> ResponsesCheckLists;
//getters and setters

 @JsonIgnore
public Collection<ResponsesCheckLists> getResponsesCheckLists() {
    return ResponsesCheckLists;
}

public void setResponsesCheckLists(Collection<ResponsesCheckLists> responsesCheckLists) {
    ResponsesCheckLists = responsesCheckLists;
   }
}

ResponsesCheckLists.java

@Entity
public class ResponsesCheckLists implements Serializable{

    @Id
    @GeneratedValue(strategy=GenerationType.IDENTITY)
    @Column(name="idResponsesCHeck")
    private long idResponsesCHeck;

    @ManyToOne
    @JoinColumn(name="missionsId")
    private Missions Respmission;

    @ManyToOne
    @JoinColumn(name="checkLists_Id")
    private CheckLists CheckLts;
     //getters and setters

     public Missions getRespmission() {
        return Respmission;
    }

    public void setRespmission(Missions respmission) {
        Respmission = respmission;
    }

    public CheckLists getCheckLts() {
        return CheckLts;
    }

    public void setCheckLts(CheckLists checkLts) {
        CheckLts = checkLts;
    }

}

StatistisquesMessions.java

@Entity
public class StatistisquesMessions implements Serializable {

    @Id
    @GeneratedValue(strategy=GenerationType.IDENTITY)
    @Column(name="idStat")
    private long idStat;

    //@ManyToOne(fetch = FetchType.EAGER, cascade = CascadeType.ALL)
    @ManyToOne
    @JoinColumn(name="equipement_ids")
    @JsonBackReference
    private Equipements statEquipements;

    @ManyToOne
    @JoinColumn(name="statMission_id")
    @JsonBackReference
    private Missions statMissions;
}

当我想从 MySQL 数据库中删除 Missions 时，如下所示（API REST）：

@Override
    public Boolean DeleteT(Pk id) {

        T tt= GR.findOne(id);
        GR.delete(tt);
        return true;
    }
@Autowired
    private MissionsMetier missionM;

@RequestMapping(value="/DeleteMissions")
    public Missions DeleteMissions(@Param(value ="idMission") long idMission){
        Missions mis = missionM.getT(idMission);     //I have the object "Missions"
        return missionM.DeleteT(idMission);
        }

然后我得到以下错误

无法删除或更新父行：外键约束失败 (BDTasks.responses_check_lists, 约束 FK73o6po4goa6ulera1d6md58i6 外键 (missions_id) 参考 missions (id_mission))

休眠查询：

Hibernate: select stat0_.stat_mission_id as stat_mis8_9_0_, stat0_.id_stat as id_stat1_9_0_, stat0_.id_stat as id_stat1_9_1_, stat0_.nbre_conforme as nbre_con2_9_1_, stat0_.nbre_not_conforme as nbre_not3_9_1_, stat0_.res_conforme as res_conf4_9_1_, stat0_.res_not_conforme as res_not_5_9_1_, stat0_.equipement_ids as equipeme7_9_1_, stat0_.stat_mission_id as stat_mis8_9_1_, stat0_.total_check_lists as total_ch6_9_1_, equipement1_.id_equipements as id_equip1_3_2_, equipement1_.actifs_id as actifs_i5_3_2_, equipement1_.date_ajout_eq as date_ajo2_3_2_, equipement1_.date_modification_eq as date_mod3_3_2_, equipement1_.nom_eq as nom_eq4_3_2_, actifs2_.id_actif as id_actif1_0_3_, actifs2_.date_ajout_actif as date_ajo2_0_3_, actifs2_.nom_actif as nom_acti3_0_3_ from statistisques_messions stat0_ left outer join equipements equipement1_ on stat0_.equipement_ids=equipement1_.id_equipements left outer join actifs actifs2_ on equipement1_.actifs_id=actifs2_.id_actif where stat0_.stat_mission_id=?
Hibernate: delete from statistisques_messions where id_stat=?
Hibernate: delete from missions where id_mission=?

编辑1：

@Autowired
    private MissionsMetier missionM;

    @RequestMapping(value="/DeleteMissions")
    public Missions DeleteMissions(@Param(value ="idMission") long idMission){
        Missions mis = missionM.getT(idMission);     //I have the object "Missions"
          // delete ResponsesCheckLists
    Collection<ResponsesCheckLists> Rp = res.FinsRespoCHeckListsMission(idMission);
    for(ResponsesCheckLists r : Rp){
        System.out.println("***** id response "+r.getIdResponsesCHeck());
         res.DeleteT(r.getIdResponsesCHeck());
     }

     //delete StatistisquesMessions
     Collection<StatistisquesMessions> st =mis.getStat(); 
     for(StatistisquesMessions stat : st){
              statis.DeleteT(stat.getIdStat());
          }

    mis.removeMissionsFromUsers();
   // return  missionM.DeleteT(idMission);
    //return true;
    return missionM.DeleteT(idMission); 

   return  missionM.DeleteT(idMission);

        }

我也有同样的问题

编辑2：

@Autowired
    private MissionsMetier missionM;

    @RequestMapping(value="/DeleteMissions")
    public Missions DeleteMissions(@Param(value ="idMission") long idMission){
        Missions mis = missionM.getT(idMission);     //I have the object "Missions"

        // delete ResponsesCheckLists
    Collection<ResponsesCheckLists> Rp = res.FinsRespoCHeckListsMission(idMission);
    for(ResponsesCheckLists r : Rp){
        System.out.println("***** id response "+r.getIdResponsesCHeck());
         res.DeleteT(r.getIdResponsesCHeck());
     }

     //delete StatistisquesMessions
     Collection<StatistisquesMessions> st =mis.getStat(); 
     for(StatistisquesMessions stat : st){
              statis.DeleteT(stat.getIdStat());
          }

    mis.removeMissionsFromUsers();

       return  missionM.DeleteT(mis.getIdMission());
        }

我怎样才能删除Missions 它的ResponsesCheckLists 和它的StatistisquesMessions 孩子？

非常感谢，

【问题讨论】：

您必须先删除子级，然后才能删除父级。在Missions 中找到ResponsesCheckLists 的键，然后删除ResponsesCheckLists，然后对StatistisquesMessions 执行相同操作。之后，您可以毫无错误地删除您的Missions。
我也遇到了同样的问题，谢谢咨询上次更新@TuyenNguyen
我认为您的代码仍然错误。 mis.removeMissionsFromUsers(); 有什么作用？为什么在删除ResponsesCheckLists 和StatistisquesMessions 之前必须调用它？
@TuyenNguyen 这个功能mis.removeMissionsFromUsers() 允许清空分配给任务的用户列表而不删除用户。 @PreRemove public void removeMissionsFromUsers() { for (Users u : employees) { u.getMissions().remove(this); } }
您是否尝试过调试？哪一行是导致错误的点？

标签： java mysql hibernate jpa

【解决方案1】：

问题通过以下代码解决：

@RequestMapping(value="/DeleteMissions")
    public Missions DeleteMissions(@Param(value ="idMission") long idMission){
        Missions mis = missionM.getT(idMission);     //I have the object "Missions"

        // delete ResponsesCheckLists
        Collection<ResponsesCheckLists> Rp = res.FinsRespoCHeckListsMission(idMission);
        for(ResponsesCheckLists r : Rp){
                r.getCheckLts().setResponsesChecks(null);
                r.setCheckLts(null);
               res.saveT(r);
               res.DeleteT(r.getIdResponsesCHeck());
         }

         //delete StatistisquesMessions
         Collection<StatistisquesMessions> st =mis.getStat(); 
         for(StatistisquesMessions stat : st){
                  statis.DeleteT(stat.getIdStat());
        }   

       return  missionM.DeleteT(idMission);
        }

【讨论】：