使用py2neo neo4j更新属性关系

时间:2018-06-01 16:02:13

标签: python neo4j py2neo

我正在尝试检查两个节点之间是否存在关系,但是我收到了这个错误:

raise TypeError("Nodes for relationship match end points must be bound") TypeError: Nodes for relationship match end points must be bound

在我的代码下面:

graph = Graph(user='neo4j')

src = Node(src_type, internal_id=int(src_id))
dst = Node(dst_type, internal_id=int(dst_id))

src_voted_dst = Relationship(src, "VOTED", dst)

for elem in graph.match(start_node=src, rel_type="VOTED", end_node=dst, bidirectional=True):
    elem.properties["vote"] = elem.properties["vote"] + 1
    elem.push()
    break
else:
    src_voted_dst.properties["vote"] = 1
    graph.merge(src_voted_dst)

1 个答案:

答案 0 :(得分:0)

在代码中:

src = Node(src_type, internal_id=int(src_id))
dst = Node(dst_type, internal_id=int(dst_id))

src和dst是在本地创建的,但不绑定到数据库中的这些节点。 使用merge将本地节点绑定到数据库:

db_src = graph.merge(src)
db_dst = graph.merge(dst)

然后匹配应该起作用:

for elem in graph.match(db_src, "VOTED", db_dst)

(注意elem.properties [“vote”]不起作用,应该有链接elem.start_node()[“vote”]或elem.end_node()[“vote”])