python使用py2neo创建neo4j的节点和关系
时间：2022-10-17 11:20:35 | 栏目：Python代码 | 点击：次
1.核心代码
使用py2neo连接neo4j的方法：
from py2neo import Graph
graph = Graph("http://localhost:7474", auth=("neo4j", "neo4j"))
graph.delete_all() # 删除已有的所有内容
根据dict创建Node：
from py2neo import Node
node = Node(**{"key":"value"})
graph.create(node)
创建关系：
from py2neo import Relationship relation = Relationship(node1, relation, node2) graph.create(relation)
用到的工具函数是：
def create_relation(graph, match_node1: dict, match_node2: dict, relation: str, node1_label=None, node2_label=None): """自动创建节点与关系 :param graph: 图 :param match_node1: 节点1属性 :param match_node2: 节点2属性 :param relation: 关系 :param node1_label: 节点1的标签 :param node2_label: 节点2的标签 """ from py2neo import Node, Relationship from py2neo import NodeMatcher node_matcher = NodeMatcher(graph) node1 = node_matcher.match(**match_node1).first() # 自动创建node if not node1: if node1_label: node1 = Node(node1_label, **match_node1) else: node1 = Node(**match_node1) node2 = node_matcher.match(**match_node2).first() if not node2: if node2_label: node2 = Node(node2_label, **match_node2) else: node2 = Node(**match_node2) # 创建关系 relation = Relationship(node1, relation, node2) graph.create(relation)
2.完整示例代码
def create_relation(graph, match_node1: dict, match_node2: dict, relation: str, node1_label=None, node2_label=None):
"""自动创建节点与关系
:param graph: 图
:param match_node1: 节点1属性
:param match_node2: 节点2属性
:param relation: 关系
:param node1_label: 节点1的标签
:param node2_label: 节点2的标签
"""
from py2neo import Node, Relationship
from py2neo import NodeMatcher
node_matcher = NodeMatcher(graph)
node1 = node_matcher.match(**match_node1).first()
# 自动创建node
if not node1:
if node1_label:
node1 = Node(node1_label, **match_node1)
else:
node1 = Node(**match_node1)
node2 = node_matcher.match(**match_node2).first()
if not node2:
if node2_label:
node2 = Node(node2_label, **match_node2)
else:
node2 = Node(**match_node2)
# 创建关系
relation = Relationship(node1, relation, node2)
graph.create(relation)
def main():
from py2neo import Graph
graph = Graph("http://localhost:7474", auth=("neo4j", "neo4j"))
graph.delete_all() # 删除已有的所有内容
create_relation(graph, {"name": "小a", "age": 12}, {"name": "小b", "age": 22}, "relation1", )
create_relation(graph, {"name": "小a", "age": 12}, {"name": "小c", "age": 32}, "relation2", "people", "people")
create_relation(graph, {"name": "小c", "age": 32}, {"name": "小d", "age": 42}, "relation1", "people", "people")
if __name__ == '__main__':
main()
效果图：
