我正在使用海王星的图形数据库和通过python进行gremlin查询，以将地址存储在数据库中。大多数查询执行正常，但是一旦我尝试以下查询，neptune就会返回内部故障异常：
g.V(address).outE('isPartOf').inV().
dedup().as_('groupNode').
inE('isPartOf').outV().dedup().as_('children').
addE('isPartOf').to(group).
select('groupNode').drop().
fold().
coalesce(__.unfold(),
g.V(address).addE('isPartOf').to(group)).next()
每个地址都有可能属于一个组。 当地址已经分配给一个组时，我尝试获取分配给该组的所有地址并将它们分配给新组，同时删除旧组。如果地址尚未分配给组，我只想立即将地址分配给新组。
如果我在它自己的上尝试此查询，一切都可以完美执行(尽管查询有点慢(。但是，一旦我尝试在更多地址上并行执行此查询，此查询就会失败并显示以下错误：
Traceback (most recent call last):
File "/usr/lib64/python2.7/threading.py", line 804, in __bootstrap_inner
self.run()
File "gremlinExample.py", line 30, in run
processTx(self.tx, self.g, self.parentBlock)
File "gremlinExample.py", line 152, in processTx
g.V(address).outE('isPartOf').inV().dedup().as_('groupNode').inE('isPartOf').outV().dedup().as_('children').select('children').addE('isPartOf').to(group).select('groupNode').drop().fold().coalesce(__.unfold(), g.V(address).addE('isPartOf').to(group)).next()
File "/home/ec2-user/.local/lib/python2.7/site-packages/gremlin_python/process/traversal.py", line 70, in next
return self.__next__()
File "/home/ec2-user/.local/lib/python2.7/site-packages/gremlin_python/process/traversal.py", line 43, in __next__
self.traversal_strategies.apply_strategies(self)
File "/home/ec2-user/.local/lib/python2.7/site-packages/gremlin_python/process/traversal.py", line 346, in apply_strategies
traversal_strategy.apply(traversal)
File "/home/ec2-user/.local/lib/python2.7/site-packages/gremlin_python/driver/remote_connection.py", line 143, in apply
remote_traversal = self.remote_connection.submit(traversal.bytecode)
File "/home/ec2-user/.local/lib/python2.7/site-packages/gremlin_python/driver/driver_remote_connection.py", line 54, in submit
results = result_set.all().result()
File "/usr/lib/python2.7/site-packages/concurrent/futures/_base.py", line 405, in result
return self.__get_result()
File "/usr/lib/python2.7/site-packages/concurrent/futures/_base.py", line 357, in __get_result
raise type(self._exception), self._exception, self._traceback
GremlinServerError: 500: {"requestId":"a42015b7-6b22-4bd1-9e7d-e3252e8f3ab6","code":"InternalFailureException","detailedMessage":"Can not get the attachable from the host vertex: v[64b32957-ef71-be47-c8d7-0109cfc4d9fd]-/->neptunegraph[org.apache.commons.configuration.PropertiesConfiguration@6db0f02]"}
据我所知，并行执行应该不是问题，因为每个查询都只是在数据库中排队(正是出于这个原因，我试图创建一个一次执行整个任务的查询(。
任何英语不好的借口，这不是我的母语
对于在这里寻找更新的任何其他人 - OP 能够通过将 .next(( 替换为 .iterate(( 来解决此问题。需要一些后续工作来更好地理解查询和数据，但OP已经放弃了该项目并转向了另一个解决方案。