Neo4j Cypher:查找一组匹配节点之间的公共节点 [英] Neo4j Cypher: Find common nodes between a set of matched nodes

问题描述

与此处发布的问题非常相似

我有以下节点:文章和单词.每个单词都通过 MENTIONED 关系与文章相关联.

I have the following nodes: Article and Words. Each word is connected to an article by a MENTIONED relationship.

我需要查询所有包含常用词的文章，其中常用词列表是动态的.从客户的角度来看，我正在传递一个单词列表，并期望返回具有这些单词的文章的结果.

I need to query all articles that have common words where the list of common words is dynamic. From the clients perspective, I am passing back a list of words and expecting back a results of articles that have those words in common.

以下查询完成工作

WITH ["orange", "apple"] as words
MATCH (w:Word)<-[:MENTIONED]-(a:Article)-[:MENTIONED]->(w2:Word)
WHERE w.name IN words AND w2.name IN words
RETURN a, w, w2

但不适用于单词列表之一.我怎样才能让它处理任意数量的单词?有没有更好的方法来做到这一点?

but does not work with word list of one. How can I make it handle any number of words? Is there a better way to do this?

推荐答案

是的.我能想到的方法有两种:

Yes. There are two approaches I can think of:

1. 查找包含这些词的某个子集的所有文章，然后仅返回提及的词数与您在词表中提供的词数相同的文章.

1. Finding all articles that contain some subset of those words, and then returning only articles where the number of words mentioned is the number of words you supplied in your wordlist.

获取给定单词列表的 :Word 节点，然后获取文章中提及所有单词的文章.

Getting the :Word nodes for the given list of words, and then getting articles where all words are mentioned in the article.

这是一个用于测试的示例图:

Here's an example graph to test this on:

MERGE (a1:Article {name:'a1'}), 
      (a2:Article {name:'a2'}), 
      (a3:Article {name:'a3'})
MERGE (w1:Word{name:'orange'}), 
      (w2:Word{name:'apple'}), 
      (w3:Word{name:'pineapple'}), 
      (w4:Word{name:'banana'})
MERGE (a1)-[:MENTIONED]->(w1), 
      (a1)-[:MENTIONED]->(w2), 
      (a1)-[:MENTIONED]->(w3), 
      (a1)-[:MENTIONED]->(w4),
      (a2)-[:MENTIONED]->(w1), 
      (a2)-[:MENTIONED]->(w4),
      (a3)-[:MENTIONED]->(w1), 
      (a3)-[:MENTIONED]->(w2),
      (a3)-[:MENTIONED]->(w3)

方法 1，将词表大小与文章中提到的词数进行比较，如下所示:

Approach 1, comparing the wordlist size to the number of words mentioned in the article, looks like this:

WITH ["orange", "apple"] as words
MATCH (word:Word)<-[:MENTIONED]-(article:Article)
WHERE word.name IN words
WITH words, article, COUNT(word) as wordCount
WHERE wordCount = SIZE(words)
RETURN article

这仅在文章和提及的词之间只有一个 :MENTIONED 关系时才有效，无论该词被提及多少次.

This only works if there is ever only one :MENTIONED relationship between an article and a mentioned word, no matter how many times that word is mentioned.

方法 2 对 :Words 的集合使用 ALL() 以确保我们匹配提及所有单词的文章:

Approach 2 is using ALL() on the collection of :Words to ensure that we match on an article where all words are mentioned:

WITH ["orange", "apple"] as words
MATCH (word:Word) 
WHERE word.name in words
WITH COLLECT(word) as words
MATCH (article:Article)
WHERE ALL (word in words WHERE (word)<-[:MENTIONED]-(article))
RETURN article

您可以尝试将 PROFILE 与其中的每一个一起使用，以确定哪个最适合您的数据集.

You can try using PROFILE with each of these to figure out which works best with your data set.

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