neo4j - 在 Neo4j Cypher 的 RETURN 语句中使用WITH语句之前的变量

Question

我从 Neo4j (v2.1.5) 开始，但在使用以下 Cypher 查询时遇到问题:

MATCH (actor:Person{name:"Tom Cruise"})-[role:ACTED_IN]->(movies)<-[r:ACTED_IN]-(coactors)
WITH  coactors, count(coactors) as TimesCoacted
RETURN coactors.name, avg(TimesCoacted)
ORDER BY avg(TimesCoacted) DESC

它是基于Neo4j安装时附带的迷你电影图。

一切正常，它显示了所有与汤姆·克鲁斯合作电影的合作 Actor 以及他们合作了多少次，但是当我想要时就会出现问题列出他们合作过的电影。将“movies”变量放在 RETURN 语句中会引发以下错误:

movies not defined (line 3, column 9)
"RETURN  movies, coactors.name, avg(TimesCoacted)"
         ^

有什么办法可以在一个查询中完成它吗？

Answer 1

尝试以下操作:

MATCH 
    (actor:Person{name:"Tom Cruise"})-[role:ACTED_IN]->(movies)<-[r:ACTED_IN]-(coactors)
WITH 
    coactors, 
    count(coactors) as TimesCoacted, 
    movies // You have declare "movies" here in order to use it later in the query
RETURN 
    movies, 
    coactors.name, 
    avg(TimesCoacted)
ORDER BY 
    avg(TimesCoacted) DESC

您在 WITH 语句中定义的内容是唯一可用于进一步处理的内容。在最初的问题中，movies 没有进入下一部分(它不是 WITH 的一部分)，因此无法使用 movies在返回语句中。

编辑:在 OP 更新后添加了以下内容。

另一个例子。如果您想计算 Actor 在电影中合作的次数并列出电影标题。请尝试以下操作:

MATCH 
    (actor:Person {name:"Tom Cruise"})-[:ACTED_IN]->(movie)<-[:ACTED_IN]-(coactor:Person)
WITH
    actor,
    coactor,
    collect (distinct movie.title) as movieTitles
RETURN
    actor.name as actorName, 
    coactor.name as coactorName, 
    movieTitles, 
    size(movieTitles) as numberOfMovies