如何在py2neo中將參數傳遞給密碼查詢

Question

我有一個變量 name="Rahul"，並且我想通過以下方式將此變量傳遞給 Py2neo 中的密碼查詢：

line=session.execute("MATCH (person)WHERE person.name=name RETURN person")

但我收到一個錯誤-

"py2neo.cypher.InvalidSyntax: name not defined (line 1, column 33)"

如何在py2neo中傳遞變量

Answer 1

如果name是參數，則需要將其括在花括號中。 您的查詢應該類似於

MATCH (person) WHERE person.name = {name} RETURN person

您的 Python 代碼可能如下所示

graph_db = neo4j.GraphDatabaseService()
qs = 'MATCH (person) WHERE person.name = {name} RETURN person'
query = neo4j.CypherQuery(graph_db, qs)
results = query.execute(name='Rahul')
print results

Answer 2

如果您想將查詢包裝在事務中，可以使用cypher模塊創建會話，然后創建事務對象。 執行此操作的語法與stephenmuss的答案中提到的neo4j.CypherQuery中的語法略有不同。

from py2neo import neo4j, cypher
graph_db = neo4j.GraphDatabaseService('http://localhost:7474/db/data/')

# Create a Session
session = cypher.Session('http://localhost:7474')
# Create a transaction
tx = session.create_transaction()

# Write your query, and then include it in the transaction with a dictionary
# of parameters.
qs = 'MATCH (person) WHERE person.name = {name} RETURN person'
tx.append(qs, parameters={'name': 'Rahul'})
results = tx.commit()

Answer 3

獲取節點的另一種方法是：

from py2neo import Graph, authenticate

server = "localhost:7474"

# set up authentication parameters
authenticate(server, <user>, <password>)

graph = Graph("{0}/db/data".format(server))
results = graph.find("person", "name", "Rahul")

Answer 4

為了清楚起見，將參數傳遞給 py2neo 查詢的通用答案是這樣的：

from py2neo import Graph

graph = Graph("URI", auth=("USER", "PASSWORD"))
graph.run("MATCH (p:Person) WHERE p.name=$name RETURN p", parameters={'name': 'Rahul'})

（注意 $ 符號）