Python操作neo4j库py2neo使用之py2neo 删除及事务相关操作（三）

py2neo 删除

1、连接数据库

from py2neo import Graph
graph = Graph("bolt://xx.xx.xx.xx:7687", auth=(user, pwd), name='neo4j')

2、删除节点

# 删除单个节点
node = graph.nodes.match(label='公司'，name='XX公司').first()
graph.delete(node)
 
# 删除多个节点
nodes = graph.nodes.match(label='公司'，name='XX公司').all()
for node in nodes:
    graph.delete(node)

3、删除关系

relationship = graph.relationships.match(r_type='投资').first()
graph.delete(relationship)
 
relationships = graph.relationships.match(r_type='投资').all()
for relationship in relationships:
    graph.delete(relationship)

4、删除所有的数据和节点

graph.delete_all()

5、删除数据库

from py2neo.database import SystemGraph
system = SystemGraph("bolt://xx.xx.xx.xx:7687", auth=(user, pwd))
system.run(f'drop database {graph_name}')

py2neo 事务

from py2neo import Graph, Node, Relationship
from py2neo.database import Transaction
graph = Graph("bolt://xx.xx.xx.xx:7687", auth=(user, pwd), name='neo4j')
 
# 创建事务
tn:Transaction = self.graph.begin()
# 创建节点
node1 = Node(label='公司', name='百度')
node2 = Node(label='公司', name='爱奇艺')
tn.create(node1)
tn.create(node2)
tn.graph.commit()
 
# 创建关系
relationship = Relationship(node1,"投资",node2，**{'金额':100000})
tn.create(relationship)
 
# 提交
tn.graph.commit()
 
# 合并节点
tn.merge()
 
# 删除节点、关系
tn.delete()
 
# 回滚
tn.graph.rollback()

py2neo 其他操作

1、执行原生cyther语句

from py2neo import Graph
graph = Graph("bolt://100.100.20.55:7687", auth=(user, pwd), name='neo4j')
 
# 获取label为公司，名称为XX公司的节点
graph.run("Match (n:`公司`) where n.name=`XX公司` return n")