使用UNION时ORDER BY中的ExecutionFailure“未知标识符”

Question

我一直对以下循环查询返回的错误感到困惑：

MATCH (p1:Person)-[r_ptq]->(tq:Ticket)
WHERE tq.name IN ["music", "sports", "movie"]
RETURN distinct(p1) AS person, count(r_ptq) AS score, collect(tq.name) AS tickets
ORDER BY score DESC LIMIT 10

UNION

MATCH (t:Ticket)<-[r_ttq]-(tq:Ticket)
WHERE tq.name IN ["music", "sports", "movie"]
WITH distinct(t), sum(r_ttq.weight) AS weight
ORDER BY weight DESC LIMIT 50
MATCH (t)<--(p:Person)
RETURN distinct(p) AS person, sum(weight) AS score, collect(t.name) AS tickets
ORDER BY score DESC LIMIT 10

这将始终返回

Unknown identifier `score`.

显然，在将查询与UNION组合时，ORDER BY指令中的标识符"score“无法识别。如果我分别运行这两个查询(在UNION之上和之下，这将非常好地工作。另外，如果我删除ORDER BY指令，它将与UNION一起工作，但这当然会改变行为。

任何关于如何解决这个问题的建议都是非常感谢的。

我调整了上面的例子来处理console.neo4j.org上的图形

MATCH (p1:Crew)-[r_ptq]->(tq:Crew)
WHERE tq.name IN ["Neo", "Morpheus"]
RETURN distinct(p1) AS person, count(r_ptq) AS score, collect(tq.name) AS tickets
ORDER BY score DESC
LIMIT 10
UNION
MATCH (t:Crew)<-[r_ttq]-(tq:Crew)
WHERE tq.name IN ["Neo", "Morpheus"]
WITH distinct(t), count(r_ttq) AS weight
ORDER BY weight DESC
LIMIT 50
MATCH (t)<--(p:Crew)
RETURN distinct(p) AS person, sum(weight) AS score, collect(t.name) AS tickets
ORDER BY score DESC
LIMIT 10

并返回Error: org.neo4j.graphdb.NotFoundException: Unknown identifier 'weight'.

在没有UNION的情况下很好地运行查询。

Answer 1

Cypher查询在语法上是正确的，并且可以在Neo4j浏览器中工作。console.neo4j.org的控制台似乎有一些JavaScript RegEx验证，在跟踪联合与的标识符时有一个错误。我们将研究这个bug并在控制台中修复它。

现在，请通过从http://www.neo4j.org/download下载Neo4j来使用Neo4j 2.0浏览器。