Neo4j:基于聚合函数过滤节点 [英] Neo4j: Filter nodes based on aggregate function

问题描述

假设我有一个客户节点列表和每个客户放置的订单列表，表示为与这些客户节点关联的订单节点.每个订单都有与之关联的费用数字属性.

Suppose I have a list of customer nodes and a list of orders each customer has placed represented as order nodes associated to these customer nodes. Each order has a cost numeric property associated to it.

我想退回那些平均订单量大于阈值的客户.这是一些无法正常运行的代码，可以例证我想要的内容:

I want to return those customers, whose average order is greater than a threshold. Here is some non-functioning code that exemplifies what I want:

MATCH (n0:Customer)-[]-(n1:Order)
WITH n1.cost as cost
WHERE avg(cost) > 300
RETURN n0, avg(cost)

但是，这当然不是很正确.我该怎么办?

But of course this is not quite right. How should I go about it?

推荐答案

您所拥有的很接近，您只需要在WITH语句中进行聚合，而不是在WHERE子句中进行

What you have is close, you just need to do the aggregation in the WITH statement, not the WHERE clause

MATCH (n0:Customer)-[]-(n1:Order)
WITH n0, avg(n1.cost) AS cost WHERE cost > 300
RETURN n0, cost

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