neo4j 查询结果根据 return 节点和属性更改

Question

我有一个包含 2 个不同 return 节点的查询。我的问题是为什么当我 return m2 节点时，结果会改变，而当从 return 语句中删除 m2 节点时，结果也会改变。结果 dcount 通过删除或添加 m2 进行更改。我的问题是为什么？！！

在 return 语句中使用 m2 的第一个查询：

MATCH (a1:Example)<-[r1:REL_EXAMPLE]-(a2:Example),
      (a1)-[:REL_2_EXAMPLE]->(m1:Mexample),
      (a2)-[:REL_2_EXAMPLE]->(m2:Mexample)
WHERE a1.key = 123456
      AND a2.key <> a1.key
      AND (r1.delta < 300 AND r1.delta > 20)
      AND ((a1.love <> 0 OR a2.love <> 0) OR (abs(a1.love - a2.love) < 0.1))
WITH a1,a2,m1,m2,r1, CASE
WHEN exists((m1)<-[:REL_2_EXAMPLE]-(a2)) OR exists((m2)<-[:REL_2_EXAMPLE]-(a1)) THEN 0.20
      ELSE 1
  END AS factor
RETURN count(r1) * factor as dcount,a2.title as anode, a2.key as id, m2.full_name ORDER BY dcount DESC LIMIT 30;

第二个查询没有 m2:

MATCH (a1:Example)<-[r1:REL_EXAMPLE]-(a2:Example),
      (a1)-[:REL_2_EXAMPLE]->(m1:Mexample),
      (a2)-[:REL_2_EXAMPLE]->(m2:Mexample)
WHERE a1.key = 123456
      AND a2.key <> a1.key
      AND (r1.delta < 300 AND r1.delta > 20)
      AND ((a1.love <> 0 OR a2.love <> 0) OR (abs(a1.love - a2.love) < 0.1))
WITH a1,a2,m1,m2,r1, CASE
WHEN exists((m1)<-[:REL_2_EXAMPLE]-(a2)) OR exists((m2)<-[:REL_2_EXAMPLE]-(a1)) THEN 0.20
      ELSE 1
  END AS factor
RETURN count(r1) * factor as dcount,a2.title as anode, a2.key as id ORDER BY dcount DESC LIMIT 30;

Answer 1

发生这种情况是因为您正在 return 语句中执行聚合操作。在 return 语句中使用 m2 的第一个查询中。

RETURN count(r1) * factor as dcount,a2.title as anode, a2.key as id, m2.full_name ORDER BY dcount DESC LIMIT 30;

dcount 是针对 a2.title、a2.key 和 m2.full_name.

的每个不同组合计算的

在第二个查询中，使用 return 语句

RETURN count(r1) * factor as dcount,a2.title as anode, a2.key as id ORDER BY dcount DESC LIMIT 30;

计算

dcount，对于a2.title和a2.key的每个不同组合，由于每个查询的聚合条件不同，因此结果不同。

neo4j 查询结果根据 return 节点和属性更改

neo4j query result changed base on return node and properties

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