Neo4j-cypher和Ruby gem返回的结果存在意外差异

我有两个节点，User和Thema（这是书籍的分类标准）

这是我与这件事有关的课程

用户：

Thema：

class Thema
  include Neo4j::ActiveNode
  property :code,     type: String, constraint: :unique
  property :subject,  type: String, constraint: :unique

  validates :code,    presence: true
  validates :subject, presence: true

  has_many  :out, :qualifiers,  rel_class: :QualifiedBy
  has_many  :in,  :users,       rel_class: :QualifiedFor
end

符合以下条件：

class QualifiedFor
  include Neo4j::ActiveRel

  from_class :User
  to_class   :Thema

  property  :qualified_as,   type: String, default: 'Reader'

  validates               :qualified_as,  presence: true
  validates_inclusion_of  :qualified_as, :in => ['Academic', 'Author', 'Critic', 'Expert', 'Enthusiast', 'Publisher', 'Reader']
end

以下是我在rails控制台中运行的内容：

irb(main):021:0> u = User.create name: 'Levi'
 CYPHER 724ms CREATE (n:`User` {props}) RETURN ID(n) | {:props=>{:uuid=>"432a58ca-1759-4b1c-92f9-0cd719140598", :name=>"Levi", :created_at=>1446056265, :updated_at=>1446056265}}
=> #<User uuid: "432a58ca-1759-4b1c-92f9-0cd719140598", created_at: Wed, 28 Oct 2015 18:17:45 +0000, name: "Levi", updated_at: Wed, 28 Oct 2015 18:17:45 +0000>
irb(main):022:0> t = Thema.find_by(code: 'AVLP')
 CYPHER 126ms MATCH (n:`Thema`) WHERE (n.code = {n_code}) RETURN n LIMIT {limit_1} | {:n_code=>"AVLP", :limit_1=>1}
=> #<Thema uuid: nil, code: "AVLP", subject: "Popular music">
irb(main):023:0> t.users << u
 CYPHER 122ms MATCH start, end WHERE (ID(start) = {ID_start}) AND (ID(end) = {ID_end}) CREATE start<-[rel1:`QUALIFIED_FOR`]-end | {:ID_start=>131, :ID_end=>1969}
=> #<QueryProxy Thema#users CYPHER: "MATCH thema131 WHERE (ID(thema131) = {ID_thema131}) MATCH thema131<-[rel1:`QUALIFIED_FOR`]-(result_users:`User`)">
irb(main):024:0> t.users.count
 Thema#users 116ms MATCH thema131 WHERE (ID(thema131) = {ID_thema131}) MATCH thema131<-[rel1:`QUALIFIED_FOR`]-(result_users:`User`) RETURN count(result_users) AS result_users | {:ID_thema131=>131}
=> 1
irb(main):025:0> t.users.each_rel.first
 Thema#users 121ms MATCH thema131 WHERE (ID(thema131) = {ID_thema131}) MATCH thema131<-[rel1:`QUALIFIED_FOR`]-(result_users:`User`) RETURN rel1 | {:ID_thema131=>131}
 CYPHER 115ms MATCH n WHERE (ID(n) = {ID_n}) RETURN n | {:ID_n=>1969}
 CYPHER 116ms MATCH n WHERE (ID(n) = {ID_n}) RETURN n | {:ID_n=>131}
=> #<QualifiedFor (:User {uuid: "432a58ca-1759-4b1c-92f9-0cd719140598"})-[:QUALIFIED_FOR]->(:Thema {uuid: nil}) qualified_as: "Reader">
irb(main):030:0* t.users.each_rel.first.qualified_as
=> "Reader"

irb（main）：021:0>u=User.create name:'Levi'
CYPHER 724ms CREATE（n:`User`{props}）返回ID（n）{:props=>{:uuid=>“432a58ca-1759-4b1c-92f9-0cd719140598”，：name=>“Levi”，：created_at=>1446056265，：updated_at=>1446056265}
=> #
irb（main）：022:0>t=Thema.find_by（代码：“AVLP”）
CYPHER 126ms MATCH（n:`Thema`）其中（n.code={n_code}）返回n LIMIT{LIMIT_1}{124;{:n_code=>“AVLP”，：LIMIT_1=>1}
=> #
irb（主要）：023:0>t.users 1969}
=> #
irb（主）：024:0>t.users.count
Thema#用户116ms匹配Themma131，其中（ID（Themma131）={ID#u Themma131}）匹配Themma131131}
=> 1
irb（主）：025:0>t.users.each_rel.first
Thema#用户121ms匹配Themma131，其中（ID（Themma131）={ID#u Themma131}）匹配Themma131131}
CYPHER 115ms匹配n，其中（ID（n）={ID_n}）返回n{:ID_n=>1969}
CYPHER 116ms匹配n，其中（ID（n）={ID_n}）返回n{:ID_n=>131}
=>#（：Thema{uuid:nil}）限定为：“读者”>
irb（主要）：030:0*t.users.each_rel.first.qualified_as
=>“读卡器”

返回用户“Levi”作为Thema的“阅读器”

但是，当我尝试在cypher中查找用户“Levi”是否符合条件时，我得到了“qualified as”的空值，请参见下面的查询：

neo4j-sh (?)$ match (u:User{name:'Levi'})-[r:QUALIFIED_FOR]-(t:Thema) return u.name, t.code, t.subject, r, r.qualified_as;
+----------------------------------------------------------------------------+
| u.name | t.code | t.subject       | r                     | r.qualified_as |
+----------------------------------------------------------------------------+
| "Levi" | "AVLP" | "Popular music" | :QUALIFIED_FOR[608]{} | <null>         |
+----------------------------------------------------------------------------+
1 row
34 ms

neo4j sh（？）$match（u:User{name:'Levi}）-[r:QUALIFIED_FOR]-（t:Thema）返回u.name，t.code，t.subject，r，r.QUALIFIED_as；
+----------------------------------------------------------------------------+
|u.name | t.code | t.subject | r | r.qualified|u as|
+----------------------------------------------------------------------------+
|“Levi”|“AVLP”|“流行音乐”|：符合[608]{}|
+----------------------------------------------------------------------------+
一排
34毫秒

---

这里怎么了？

是的，很抱歉

---

不幸的是，当您这样做时，

t.用户只是编辑了解决方案，说明了为什么目前这不起作用。
Neo4j
gem的主分支更改了要使用的行为
ActiveRel
如果指定为关联的
rel\u类型
。它应该是
6.0.0
neo4j-sh (?)$ match (u:User{name:'Levi'})-[r:QUALIFIED_FOR]-(t:Thema) return u.name, t.code, t.subject, r, r.qualified_as;
+----------------------------------------------------------------------------+
| u.name | t.code | t.subject       | r                     | r.qualified_as |
+----------------------------------------------------------------------------+
| "Levi" | "AVLP" | "Popular music" | :QUALIFIED_FOR[608]{} | <null>         |
+----------------------------------------------------------------------------+
1 row
34 ms

QualifiedFor.create(from_node: u, to_node: t)