Question

我试图在Python中实现这个相同的场景：https://neo4j.com/docs/developer-manual/current/cypher/clauses/create/#create-create-multiple-nodes-with-a-parameter-for-their-properties

我要做的是在图表中插入维基百科页面中的所有链接作为节点，但我在创建步骤中陷入困境。

import wikipedia
from py2neo import Graph

first_page = "United Kingdom"

page = wikipedia.page(first_page)

page_name = page.title
page_id = page.pageid
links = page.links

graph = Graph(bolt=True, password="mypassword")

nodes = {}
nodes['Page'] = list({"title" : c} for c in page.links)
node = "UNWIND {json} as data CREATE (n) SET n = data"
graph.run(node, json=nodes)

如果我打印节点字典，它的格式与Neo4j文档中上面链接中显示的格式完全相同，以供参考。

{
  "props" : [ {
    "name" : "Andres",
    "position" : "Developer"
  }, {
    "name" : "Michael",
    "position" : "Developer"
  } ]
}

但是在我的情况下，我收到以下错误消息：

py2neo.status.CypherTypeError：属性值只能是基本类型或其数组。

我试图找到一种用单个语句创建节点的方法，这是否可以使用Python？

Answer 1

错误是由于您传递的json /对象引起的。 UNWIND仅使用列表。尝试传递“ nodes ['Page'] ”而不是“节点”，如下所示。

import wikipedia
from py2neo import Graph

first_page = "United Kingdom"

page = wikipedia.page(first_page)

page_name = page.title
page_id = page.pageid
links = page.links

graph = Graph(bolt=True, password="mypassword")

nodes = {}
nodes['Page'] = list({"title" : c} for c in page.links)
node = "UNWIND {json} as data CREATE (n) SET n = data"
graph.run(node, json=nodes['Page'])

或者你可以使用python的neo4j-driver更容易。

import wikipedia
from neo4j.v1 import GraphDatabase, basic_auth

driver = GraphDatabase.driver("bolt://localhost:5687",auth=basic_auth("neo4j","neo"))
session = driver.session()

first_page = "United Kingdom"

page = wikipedia.page(first_page)

page_name = page.title
page_id = page.pageid
links = page.links

nodes = list({"title" : c} for c in page.links)

query = "UNWIND {nodes} as data CREATE (n:Test) SET n = data;"

result = session.run(query,nodes=nodes)
print result

希望这有帮助！

使用Python在Neo4j中创建具有其属性参数的多个节点

1 个答案: