Neo4j的3.0.1 SDN 4.1.1.RELEASE幻象節點

Question

在我Neo4j 3.0.1和SDN 4.1.1.RELEASE項目，我有以下實體：

@NodeEntity 
public class CriterionGroup extends Authorable { 

    private final static String DEFINED_BY = "DEFINED_BY"; 
    private final static String CONTAINS = "CONTAINS"; 

    private String name; 

    private String description; 

    @Relationship(type = DEFINED_BY, direction = Relationship.OUTGOING) 
    private Decision owner; 

    @Relationship(type = CONTAINS, direction = Relationship.OUTGOING) 
    private Set<Criterion> criteria = new HashSet<>(); 
.... 

@NodeEntity 
public class Criterion extends Authorable { 

    private final static String CONTAINS = "CONTAINS"; 
    private final static String DEFINED_BY = "DEFINED_BY"; 

    private String name; 

    private String description; 

    @Relationship(type = CONTAINS, direction = Relationship.INCOMING) 
    private CriterionGroup group; 

    @Relationship(type = DEFINED_BY, direction = Relationship.OUTGOING) 
    private Decision owner; 
.... 


@NodeEntity 
public class Decision extends Commentable { 

    private final static String CONTAINS = "CONTAINS"; 
    private final static String DEFINED_BY = "DEFINED_BY"; 
    private final static String VOTED_FOR = "VOTED_FOR"; 

    private String name; 

    @Relationship(type = CONTAINS, direction = Relationship.INCOMING) 
    private Set<Decision> parentDecisions = new HashSet<>(); 

    @Relationship(type = CONTAINS, direction = Relationship.OUTGOING) 
    private Set<Decision> childDecisions = new HashSet<>(); 

    @Relationship(type = DEFINED_BY, direction = Relationship.INCOMING) 
    private Set<CriterionGroup> criterionGroups = new HashSet<>(); 

    @Relationship(type = DEFINED_BY, direction = Relationship.INCOMING) 
    private Set<Criterion> criteria = new HashSet<>(); 
.... 

在我的測試我試圖用以下方法庫中刪除CriterionGroup：

@Query("MATCH()-[r]-(cg:CriterionGroup) WHERE id(cg) = {criterionGroupId} DELETE cg, r") 
void deleteCriterionGroup(@Param("criterionGroupId") Long criterionGroupId); 

然後我試圖通過ID來獲得這個CriterionGroup

criterionGroupRepository.findOne(id); 

並且它返回NULL。到現在爲止還挺好。

緊接着，我試圖擺脫Criterion組對象是在被刪除CriterionGroup並返回..刪除CriterionGroup

criterionRepository.findOne(criterion.getId()).getGroup() 

我在做什麼錯？一切工作正常SDN 3.4.4.RELEASE和Neo4j 2.3.3但Neo4j 3.0.1SDN 4.1.1.RELEASE由於我知識有限，我有很多意想不到的情況。

此外，有好有以下關係定義在一個實體（我已刪除enforceTargetType）

@Relationship(type = CONTAINS, direction = Relationship.INCOMING) 
private Set<Decision> parentDecisions = new HashSet<>(); 

@Relationship(type = CONTAINS, direction = Relationship.OUTGOING) 
private Set<Decision> childDecisions = new HashSet<>(); 

他們有不同的方向。

Answer 1

據我所知，您將使此CriterionGroup重新出現，因爲您通過自定義查詢刪除了它，因此繞過了OGM。該圖知道你的變化，但OGM的映射上下文不知道。 解決方案是在使用Session.detachEntity(id)通過自定義查詢刪除此實體後，從會話中註銷此實體，或者使用session.clear()刷新整個會話。

是的，它是好的，有CONTAINS關係的定義，請記住，標誌着INCOMING任何關係，如果他們@Relationship(type = CONTAINS, direction = Relationship.INCOMING)

更新存在，你必須註解存取，存取器和屬性parentDecisions：另外，還要確保您的對象模型與您通過自定義查詢刪除的內容同步。即如果您要通過自定義查詢刪除CriterionGroup，則還應更新對象模型以反映此情況，即criterion.group=null。或者，使用session.clear()完全清除會話並重新加載所有相關實體。