Neo4j 无法将GraphObject强制转换为节点
我定义了一个Neo4j 无法将GraphObject强制转换为节点,neo4j,py2neo,Neo4j,Py2neo,我定义了一个AbstractQuery,作为GraphObject的子对象: class AbstractQuery(GraphObject): __primarykey__ = "hash" hash = Property() projname = Property() def __init__(self, hash): self.hash = hash self.projname = "" # TODO:initiali
AbstractQuery
,作为GraphObject
的子对象:
class AbstractQuery(GraphObject):
__primarykey__ = "hash"
hash = Property()
projname = Property()
def __init__(self, hash):
self.hash = hash
self.projname = "" # TODO:initialize this
并在我的(已经存在的)图中的所有SQLQuery
对象上迭代,并希望创建一个新的AbstractQuery
,其中包含一个散列。任何SQLQuery
哈希到确定AbstractQuery
的哈希都应该连接:
def addAbstractionLayerSqlQueries(graph, logger=None):
abstractQueryTable = getAbstractQueries(graph, logger)
sqlqueries = graph.data("MATCH (n:SQLQuery) return n")
if logger is not None:
logger.info("abstracting {} queries".format(len(sqlqueries)))
counter = 1
for iterator in sqlqueries:
query = iterator['n']
if logger is not None:
logger.info("abstracting query {}/{}".format(counter,
len(sqlqueries)))
hash = sqlNormalizer.generate_normalized_query_hash(query['ts'])
if hash not in abstractQueryTable:
abstractQueryNode = al.AbstractQuery(hash)
abstractQueryTable[hash] = abstractQueryNode
graph.push(abstractQueryNode)
rel = Relationship(query, "ABSTRACTSTO", abstractQueryTable[hash])
graph.create(rel)
counter = counter + 1
在开始这个过程之前,我提取一个表(使用散列作为键)来包含所有已经存在的AbstractQuery,以防止创建同一个AbstractQuery两次
但是,当我运行该方法时,最终出现了一个异常:
TypeError:无法将AbstractQuery强制转换为节点
这是为什么?我如何解决这一问题?
我之前使用以下表示法在我的图表中输入了多个sqlquerys
:
class SQLQuery(GraphObject):
__primarykey__ = "uuid"
uuid = Property()
projname = Property()
session = Property()
user = Property()
seq = Property()
ts = Property()
sql = Property()
Statement = RelatedTo("SQLStatement")
AbstractsTo = RelatedTo("AbstractQuery")
def __init__(self, projname=None, session=None, user=None,
seq=None, ts=None, sql=None):
self.projname = projname
self.session = session
self.user = user
self.seq = seq
self.ts = ts
self.sql = sql
self.uuid = "{} [{} {}] {}.{}.{}".format(type(self).__name__,
seq, ts, projname,
session, user)
由于我能够使用此表示来表示和输入节点,我对py2neo为什么拒绝将我的
AbstractQuery
类作为我的addAbstractionLayerSqlQueries
函数中的节点感到非常震惊。我仅通过使用对象模型并替换图形解决了这个问题。数据(…)查询部分:
def addAbstractionLayerSqlQueries(graph, logger=None):
abstractQueryTable = getAbstractQueries(graph, logger)
sqlqueries = list(adlsql.SQLQuery.select(graph))
print type(sqlqueries)
if logger is not None:
logger.info("abstracting {} queries".format(len(sqlqueries)))
counter = 1
for query in sqlqueries:
print type(query)
if logger is not None:
logger.info("abstracting query {}/{}".format(counter,
len(sqlqueries)))
hash = sqlNormalizer.generate_normalized_query_hash(query.ts)
if hash not in abstractQueryTable:
abstractQueryNode = al.AbstractQuery(hash)
abstractQueryTable[hash] = abstractQueryNode
graph.push(abstractQueryNode)
query.AbstractsTo.add(abstractQueryTable[hash])
graph.push(query)
counter = counter + 1
然而,错误的实际原因仍然未知,我将接受任何解释这一点的答案。这个答案只是解决了问题。您混合了两层API。OGM层位于常规py2neo API之上,而
GraphObject
并不直接对应于节点(它还包含其他内容)。因此,您不能直接与图形对象
建立关系
要访问GraphObject
后面的核心节点,可以使用my\u对象