相當於密碼查詢的遍歷描述

我有一個密碼查詢，我試圖編寫等價的遍歷描述，但是我被訂單卡住了。相當於密碼查詢的遍歷描述

start n=node:EduNodes(title='bachelor of science')  
match p=n-[:JOB_CHANGE|EDUCATION|CAREER_ENTRY|EDUCATION_CONTINUED*1..4]->m  
with p, relationships(p) as rels, n, m  
return p,n,m,  
reduce(weight=0, x in rels: weight + x.weight) as totalWeight  
order by totalWeight asc

此查詢非常消耗內存和緩慢的，遍歷描述是快：

TraversalDescription td = Traversal.traversal().evaluator(Evaluators.excludeStartPosition()) 
     .uniqueness(Uniqueness.NONE).depthFirst() 
     .evaluator(Evaluators.includingDepths(1, 4)) 
     .relationships(RelationshipTypes.JOB_CHANGE, Direction.OUTGOING) 
     .relationships(RelationshipTypes.EDUCATION, Direction.OUTGOING) 
     .relationships(RelationshipTypes.CAREER_ENTRY, Direction.OUTGOING) 
     .relationships(RelationshipTypes.EDUCATION_CONTINUED, Direction.OUTGOING);

可我也有暗號查詢的最後兩行的遍歷描述（減少訂單）？我後來自己做一個循環..

Traverser traverser = td.traverse(start); 
List<PathWrapper> orderedTraversalResult = new ArrayList<>(); 
for (Path path : traverser) { 
    orderedTraversalResult.add(new PathWrapper(path)); 
} 
Collections.sort(orderedTraversalResult);

來源

2014-09-10 myborobudur

您可以提供自己的PathEvaluator是能夠處理分支狀態。最好的資源是Neo4j本身的單元測試，請查看https://github.com/neo4j/neo4j/blob/master/community/kernel/src/test/java/org/neo4j/kernel/impl/traversal/TestBranchState.java。

來源

2014-09-10 15:22:04

嗯..？我必須能夠將'totalWeight'加入'Path'。從例子中，我不能這樣做。但是，感謝鏈接！ – myborobudur 2014-09-12 11:06:55

如果這不起作用，您可以聲明一個「Map 權重」並將其填充到自定義的pathevaluator中。在遍歷結果時，可以通過'weights.get（path）'獲取給定路徑的權重。 – 2014-09-12 11:11:55

相當於密碼查詢的遍歷描述

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