Cypher 不会重复相同的结果

Question

我有一个这样的密码：

start n=node(*) 
match p=n-[r:OWES*1..200]->n 
return extract(s in relationships(p) : s.amount), 
       extract(t in nodes(p) : t.name),
       length(p)

查询返回与关系 OWES 连接的封闭圆圈中的节点，深度可达 200 级。 给出的结果是：

   2

[155.55, 100641359]

[LJUBOJEVIC STR I PRZIONA KAFE VL.LJ , SASA , LJUBOJEVIC STR I PRZIONA KAFE VL.LJ ]


2

[100641359, 155.55]

[SASA , LJUBOJEVIC STR I PRZIONA KAFE VL.LJ , SASA ]


3

[100641359, 100641367, 550111.55]

[SASA , LJUBOJEVIC STR I PRZIONA KAFE VL.LJ , ADVOKAT KOSTIC JEVREM VRBAS , SASA ]

3

[100641367, 550111.55, 100641359]

[LJUBOJEVIC STR I PRZIONA KAFE VL.LJ , ADVOKAT KOSTIC JEVREM VRBAS , SASA , LJUBOJEVIC STR I PRZIONA KAFE VL.LJ ]

3

[550111.55, 100641359, 100641367]

[ADVOKAT KOSTIC JEVREM VRBAS , SASA , LJUBOJEVIC STR I PRZIONA KAFE VL.LJ , ADVOKAT KOSTIC JEVREM VRBAS ]

所以我让我的结果返回更多次，如果是 3 个关系级别，我会得到 3 个结果，2 我会以不同的顺序得到 2 个相同的结果。如何通过不放弃来更改我的密码以在一条路径上只获得一次结果来自 * 的密码。如果不是在密码中，我可以在 Java 中以某种方式处理这个问题。

Answer 1

这里使用的是 Cypher 2.0，因为我正在使用 STARTNODE 函数。

这有点怪异，但它确实有效。如果不添加一些严格的限制以减小整体集合大小，我不会使用它。

CREATE 
    (a {name:'A'}),
    (b {name:'B'}),
    (c {name:'C'}),
    (d {name:'D'}),
    (e {name:'E'}),
    (f {name:'F'}),
    a-[:OWES {amount:100}]->b,
    b-[:OWES {amount:200}]->c,
    c-[:OWES {amount:300}]->a,
    e-[:OWES {amount:400}]->f,
    f-[:OWES {amount:500}]->e



start nn=node(*)
MATCH nn-[nr:OWES]->() 
WITH nn, nr ORDER BY nn.name, nr.amount
WITH COLLECT([nn, nr.amount]) as sortedPairs
START n=node(*)
match p=n-[r:OWES*1..200]->n
WITH sortedPairs, 
    extract(s in r: [STARTNODE(s), s.amount]) as pairs
WITH  
    filter(sp in sortedPairs: ANY(f in pairs WHERE HEAD(f) = HEAD(sp) AND LAST(f) = LAST(sp))) as finalPairs     
return distinct
    extract(s in finalPairs : HEAD(s)),
    extract(s in finalPairs : LAST(s)),
    length(finalPairs)

结果： 详细查询结果 查询结果

+----------------------------------------------------------------------------------------------------------------------+
| extract(s in finalPairs : HEAD(s))                         | extract(s in finalPairs : LAST(s)) | length(finalPairs) |
+----------------------------------------------------------------------------------------------------------------------+
| [Node[39]{name:"E"},Node[38]{name:"F"}]                    | [400,500]                          | 2                  |
| [Node[43]{name:"A"},Node[42]{name:"B"},Node[41]{name:"C"}] | [100,200,300]                      | 3                  |
+----------------------------------------------------------------------------------------------------------------------+
2 rows
13 ms

Execution Plan

Distinct(_rows=2, _db_hits=0)
ColumnFilter(symKeys=["sortedPairs", "pairs", "finalPairs"], returnItemNames=["finalPairs"], _rows=5, _db_hits=0)
  Extract(symKeys=["sortedPairs", "pairs"], exprKeys=["finalPairs"], _rows=5, _db_hits=0)
    ColumnFilter(symKeys=["n", "sortedPairs", "  UNNAMED155", "pairs", "p", "r"], returnItemNames=["sortedPairs", "pairs"], _rows=5, _db_hits=0)
      Extract(symKeys=["n", "sortedPairs", "  UNNAMED155", "p", "r"], exprKeys=["pairs"], _rows=5, _db_hits=13)
        ExtractPath(name="p", patterns=["  UNNAMED155=n-[:OWES*1..200]->n"], _rows=5, _db_hits=0)
          PatternMatch(g="(n)-['  UNNAMED155']-(n)", _rows=5, _db_hits=0)
            AllNodes(identifier="n", _rows=6, _db_hits=6)
              ColumnFilter(symKeys=["  INTERNAL_AGGREGATEfbdcf75a-046d-4501-9696-1e2c80469b29"], returnItemNames=["sortedPairs"], _rows=1, _db_hits=0)
                EagerAggregation(keys=[], aggregates=["(  INTERNAL_AGGREGATEfbdcf75a-046d-4501-9696-1e2c80469b29,Collect)"], _rows=1, _db_hits=5)
                  ColumnFilter(symKeys=["nr", "  UNNAMEDS-2101388511", "  UNNAMEDS2003458696", "nn", "  UNNAMED39"], returnItemNames=["nn", "nr"], _rows=5, _db_hits=0)
                    Sort(descr=["SortItem(Cached(  UNNAMEDS2003458696 of type Any),true)", "SortItem(Cached(  UNNAMEDS-2101388511 of type Any),true)"], _rows=5, _db_hits=0)
                      Extract(symKeys=["nn", "  UNNAMED39", "nr"], exprKeys=["  UNNAMEDS2003458696", "  UNNAMEDS-2101388511"], _rows=5, _db_hits=10)
                        PatternMatch(g="(nn)-['nr']-(  UNNAMED39)", _rows=5, _db_hits=0)
                          AllNodes(identifier="nn", _rows=6, _db_hits=6)