neo4j - py2neo - 无法在创建时将参数放入关系中

Question

If I run my python script over neo4j database, works ok:

from py2neo import Node, Relationship, Graph, cypher, authenticate

# set up authentication parameters
authenticate("localhost:7474", "user", "password")

# connect to authenticated graph database
sgraph = Graph("http://localhost:7474/db/data/")

    a=raw_input("Input Name A: ")
    b=raw_input("Input Name B: ")
    graph = Graph()
    tx = graph.cypher.begin()
    tx.append("MATCH (c:Person {name:{a}}), (d:Person {name:{b}}) CREATE (c)-[:KNOWS}]->(d)", a=a, b=b)
    tx.commit()

but, when I tried to add parameters to relationship...:

a=raw_input("Input Name A: ")
b=raw_input("Input Name B: ")
z=raw_input("Input parameter of relationship z: ")
x=raw_input("Input parameter of relationship x: ")
graph = Graph()
tx = graph.cypher.begin()
tx.append("MATCH (c:Person {name:{a}}), (d:Person {name:{b}}) CREATE (c)-[:KNOWS{labelz:{z},labelx:{x}}]->(d)", a=a, b=b)
tx.commit()

I got this:

    tx.commit()
 File "/usr/local/lib/python2.7/dist-packages/py2neo/cypher/core.py", line 333, in commit
    return self.post(self.__commit or self.__begin_commit)
 File "/usr/local/lib/python2.7/dist-packages/py2neo/cypher/core.py", line 288, in post raise self.error_class.hydrate(error)

py2neo.cypher.error.statement.ParameterMissing: Expected a parameter named z

How do I have to place those variables to avoid that errors? Thanks in advance.

Answer 1

Parameters can not be used as for property names, relationship types and labels:( link ,