Question

我有以下代码：

for t in set(tags):
    new_tag = Node('Tag', name=t)
    tag = graph.merge(new_tag, 'Tag', 'name')
    rel = Relationship(tag, 'TAGGED', post)
    graph.create(rel)

问题是graph.merge()返回None，但是documentation说如果找不到匹配项，它将创建一个新节点。

这是执行graph.create(rel)时遇到的错误：

 File "/Users/hugovillalobos/Documents/Code/FlaskrGraphProject/FlaskrGraphVenv/lib/python3.7/site-packages/py2neo/internal/operations.py", line 134, in <genexpr>
    for labels, nodes in _node_create_dict(n for n in subgraph.nodes if n.graph is None).items():
AttributeError: 'NoneType' object has no attribute 'graph'

Answer 1

合并后提交。然后创建关系。

Answer 2

您应该简单地使用：

tag = graph.merge(new_tag)

py2neo merge返回None

2 个答案: