Question

我正在过滤多个属性并获取一个节点，因此如果有多个filter与and和or联接在一起。 2个工作正常，但从第3个开始似乎崩溃了。

下面是该错误的简化说明。

使用filter

gremlin> g.V().filter(has("name", "marko"))
==>v[1]

gremlin> g.V().filter(has("name", "marko")).and().filter(has("name", "marko"))
==>v[1]

gremlin> g.V().filter(has("name", "marko")).and().filter(has("name", "marko")).and().filter(has("name", "marko"))
java.util.ConcurrentModificationException
Type ':help' or ':h' for help.
Display stack trace? [yN]

没有filter

gremlin> g.V().has("name", "marko")
==>v[1]

gremlin> g.V().has("name", "marko").and().has("name", "marko")
==>v[1]

gremlin> g.V().has("name", "marko").and().has("name", "marko").and().has("name", "marko")
java.util.ConcurrentModificationException
Type ':help' or ':h' for help.
Display stack trace? [yN]

dummy-name是不存在的。仍然因其他错误而崩溃

gremlin> g.V().hasLabel("dummy-name").filter(has("name", "a").or().has("name", "b").or().has("name", "c"))
    java.lang.ArrayIndexOutOfBoundsException
    Type ':help' or ':h' for help.
    Display stack trace? [yN]y
    java.lang.ArrayIndexOutOfBoundsException

连接到NEO4J并使用filter时，它会抛出我

test_gremlin.py", line 49, in execut_final_query
    results = future_results.result()
  File "/usr/lib/python3.6/concurrent/futures/_base.py", line 432, in result
    return self.__get_result()
  File "/usr/lib/python3.6/concurrent/futures/_base.py", line 384, in __get_result
    raise self._exception
  File "/home/admin-12/.local/lib/python3.6/site-packages/gremlin_python/driver/resultset.py", line 81, in cb
    f.result()
  File "/usr/lib/python3.6/concurrent/futures/_base.py", line 425, in result
    return self.__get_result()
  File "/usr/lib/python3.6/concurrent/futures/_base.py", line 384, in __get_result
    raise self._exception
  File "/usr/lib/python3.6/concurrent/futures/thread.py", line 56, in run
    result = self.fn(*self.args, **self.kwargs)
  File "/home/admin-12/.local/lib/python3.6/site-packages/gremlin_python/driver/connection.py", line 77, in _receive
    self._protocol.data_received(data, self._results)
  File "/home/admin-12/.local/lib/python3.6/site-packages/gremlin_python/driver/protocol.py", line 106, in data_received
    "{0}: {1}".format(status_code, data["status"]["message"]))
gremlin_python.driver.protocol.GremlinServerError: 597: None

我写错了查询吗？还是这个错误？

版本：Gremlin 3.3.1

Answer 1

我不知道为什么多个and()条件不能立即生效，尽管我想应该可以，所以我在JIRA中为此创建了一个问题：TINKERPOP-2029

这确实起作用：

gremlin> g.V().and(filter(has("name", "marko")), filter(has("name", "marko")), filter(has("name", "marko")))
==>v[1]

或更简单地说：

gremlin> g.V().and(has("name", "marko"), has("name", "marko"), has("name", "marko"))
==>v[1]

在您对所写问题的评论中，您实际上想做a和b或c和d-这种方法似乎可以实现：

gremlin> g.V().or(and(has('name','marko'),has('age',29)),and(has('name','josh'),has('age',32)))
==>v[1]
==>v[4]

，或者在这种情况下更简单地表示为：

gremlin> g.V().or(has('name','marko').has('age',29),has('name','josh').has('age',32))
==>v[1]
==>v[4]

使用和/或多个过滤器的TinkerPop问题

1 个答案: