Neo4j CQL：对于每个节点，返回最早的相关节点X

问题描述

我有类似(p:Post)-[:USED]->[e:Email] RETURN e.address,p.createdAt之类的东西会返回：

sample results screenshot

我试图为每个唯一的电子邮件地址获取最早的p.createdAt。对于上面的示例，它将是：

desired results screenshot

此外，我想知道该帖子的年限（以月为单位）。

desired results with months

我目前有这个查询，但它只是返回所有帖子和所有帖子年龄：

MATCH (p:Post)-[:USED_EMAIL]->(e:Email)
WITH p,e.address AS email
  ORDER BY p.createdAt ASC
WITH email,COLLECT(p.createdAt) AS collection
WITH email,collection[0] AS oldestPost,duration.inMonths(datetime(collection[0]),datetime()) AS durationMonths
WITH email,oldestPost,durationMonths.months AS numMonthsAgo
RETURN email,numMonthsAgo

请帮助。我正在彻底解决这个问题！

谢谢！

解决方法

尝试以下查询：

MATCH (p:Post)-[:USED_EMAIL]->(e:Email)
WITH p,e.address as email
  ORDER BY p.createdAt ASC
WITH email,collect(p.createdAt)[0] as first_post
RETURN email,first_post,duration.inMonths(datetime(collection[0]),datetime()).months AS durationMonths

cypher foreach