我已经成功地使用 Python 在 Neo4j 中显示和创建节点，但我正在努力使用 Python 更新 Neo4j 中的节点。我尝试向 ChatGPT 寻求帮助，但我仍然无法弄清楚如何更新 Neo4j 中的节点 这是Python代码
from neo4j import GraphDatabase
class Neo4jConnector:
def __init__(self, uri, user, password):
self._driver = GraphDatabase.driver(uri, auth=(user, password))
def close(self):
self._driver.close()
@property
def driver(self):
return self._driver
def create_node(neo4j_conn, sender, receiver, message, profile_id, rule_type, processing_flag, return_name):
query = (
"CREATE (n:Message {sender: $sender, receiver: $receiver, "
"message: $message, profile_id: $profile_id, rule_type: $rule_type, "
"processing_flag: $processing_flag,return_name:$return_name})"
)
with neo4j_conn._driver.session() as session:
session.write_transaction(lambda tx: tx.run(query, sender=sender, receiver=receiver,
message=message, profile_id=profile_id,
rule_type=rule_type, processing_flag=processing_flag,
return_name=return_name))
def display_nodes(neo4j_conn):
query = "MATCH (n:Message) RETURN n"
with neo4j_conn._driver.session() as session:
result = session.run(query)
for record in result:
node = record["n"]
print(node)
def get_nodes_by_processing_flag(tx, processing_flag):
query = (
"MATCH (node:Message) "
"WHERE node.processing_flag = $processing_flag "
"RETURN node"
)
result = []
for record in tx.run(query, processing_flag=processing_flag):
result.append(record["node"])
return result
def update_node(tx, new_profile_id, new_message, new_processing_flag, return_name):
query = (
"MATCH (n) WHERE return_name(n) = $return_name"
"SET n.profile_id = $new_profile_id, "
" n.message = $new_message, "
" n.processing_flag = $new_processing_flag "
)
tx.run(query, new_profile_id=new_profile_id, new_message=new_message,
new_processing_flag=new_processing_flag, return_name=return_name)
def main():
uri = "bolt://localhost:7687" # Update with your Neo4j server URI
user = "admin" # Update with your Neo4j username
password = "password" # Update with your Neo4j password
connector = Neo4jConnector(uri, user, password)
while True:
print("1. Create Node")
print("2. Display Nodes")
print("3. Get Nodes by Processing Flag")
print("4. Update Node")
print("5. Quit")
choice = input("Enter your choice: ")
if choice == "1":
sender = input("Enter sender: ")
receiver = input("Enter receiver: ")
message = input("Enter message: ")
profile_id = input("Enter profile_id: ")
rule_type = input("Enter rule_type: ")
processing_flag = input("Enter processing_flag: ")
return_name = sender + rule_type + receiver
create_node(connector, sender, receiver, message, profile_id, rule_type, processing_flag, return_name)
elif choice == "2":
display_nodes(connector)
elif choice == "3":
user_input = input("Enter the processing flag: ")
with connector._driver.session() as session:
nodes = session.read_transaction(get_nodes_by_processing_flag, user_input)
if nodes:
print(f"Nodes with processing flag '{user_input}':")
for node in nodes:
print(node)
else:
print(f"No nodes found with processing flag '{user_input}'.")
elif choice == "4":
return_name = input("Enter return name: ")
new_profile_id = input("Enter new profile_id: ")
new_message = input("Enter new message: ")
new_processing_flag = input("Enter new processing_flag: ")
with connector.driver.session() as session:
session.write_transaction(update_node, new_profile_id, new_message,
new_processing_flag, return_name)
print("Node updated successfully.")
elif choice == "5":
connector.close()
break
if __name__ == "__main__":
main()
这是代码中的错误
Traceback (most recent call last):
File "C:\Users\kevin\PycharmProjects\pyneo4j\main.py", line 120, in <module>
main()
File "C:\Users\kevin\PycharmProjects\pyneo4j\main.py", line 110, in main
session.write_transaction(update_node, new_profile_id, new_message,
File "C:\Users\kevin\PycharmProjects\pyneo4j\venv\Lib\site-packages\neo4j\_meta.py", line 209, in inner
return f(*args, **kwargs)
^^^^^^^^^^^^^^^^^^
File "C:\Users\kevin\PycharmProjects\pyneo4j\venv\Lib\site-packages\neo4j\_sync\work\session.py", line 791, in write_transaction
return self._run_transaction(
^^^^^^^^^^^^^^^^^^^^^^
File "C:\Users\kevin\PycharmProjects\pyneo4j\venv\Lib\site-packages\neo4j\_sync\work\session.py", line 550, in _run_transaction
result = transaction_function(tx, *args, **kwargs)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "C:\Users\kevin\PycharmProjects\pyneo4j\main.py", line 59, in update_node
tx.run(query, new_profile_id=new_profile_id, new_message=new_message,
File "C:\Users\kevin\PycharmProjects\pyneo4j\venv\Lib\site-packages\neo4j\_sync\work\transaction.py", line 164, in run
result._tx_ready_run(query, parameters)
File "C:\Users\kevin\PycharmProjects\pyneo4j\venv\Lib\site-packages\neo4j\_sync\work\result.py", line 116, in _tx_ready_run
self._run(query, parameters, None, None, None, None, None, None)
File "C:\Users\kevin\PycharmProjects\pyneo4j\venv\Lib\site-packages\neo4j\_sync\work\result.py", line 166, in _run
self._attach()
File "C:\Users\kevin\PycharmProjects\pyneo4j\venv\Lib\site-packages\neo4j\_sync\work\result.py", line 274, in _attach
self._connection.fetch_message()
File "C:\Users\kevin\PycharmProjects\pyneo4j\venv\Lib\site-packages\neo4j\_sync\io\_common.py", line 180, in inner
func(*args, **kwargs)
File "C:\Users\kevin\PycharmProjects\pyneo4j\venv\Lib\site-packages\neo4j\_sync\io\_bolt.py", line 851, in fetch_message
res = self._process_message(tag, fields)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "C:\Users\kevin\PycharmProjects\pyneo4j\venv\Lib\site-packages\neo4j\_sync\io\_bolt5.py", line 376, in _process_message
response.on_failure(summary_metadata or {})
File "C:\Users\kevin\PycharmProjects\pyneo4j\venv\Lib\site-packages\neo4j\_sync\io\_common.py", line 247, in on_failure
raise Neo4jError.hydrate(**metadata)
neo4j.exceptions.CypherSyntaxError: {code: Neo.ClientError.Statement.SyntaxError} {message: Invalid input 'n': expected
"!="
"%"
"*"
"+"
"-"
"."
"/"
":"
"<"
"<="
"<>"
"="
"=~"
">"
">="
"AND"
"CALL"
"CONTAINS"
"CREATE"
"DELETE"
"DETACH"
"ENDS"
"FOREACH"
"IN"
"IS"
"LOAD"
"MATCH"
"MERGE"
"OPTIONAL"
"OR"
"REMOVE"
"RETURN"
"SET"
"STARTS"
"UNION"
"UNWIND"
"USE"
"WITH"
"XOR"
"["
"^"
<EOF> (line 1, column 50 (offset: 49))
"MATCH (n) WHERE return_name(n) = $return_nameSET n.profile_id = $new_profile_id, n.message = $new_message, n.processing_flag = $new_processing_flag"
^}
代码 return_name(n) 应该是 n.return_name