Tinkerpop Gremlin表达

Question

在上图中,我有用户,客户端,站点和作业.用户连接到客户端(管理)和客户端(有) - >站点(有)--->作业.我正在努力让所有有活跃工作的客户.

g.V().hasLabel('user').
      has('id', '338d219c-3457-4ad8-8172-37a7d897c0df').
      outE('manages').
      inV().
      hasLabel('client').
      outE('have').
      inV().
      hasLabel('site').
      outE('have').
      inV().
      hasLabel('job').
      has('status', 'In Progress')

以上查询获取所有工作,但我有兴趣了解客户端,站点和工作.我想知道如何实现这一目标？

Answer 1

你可能没有多少方法可以做到这一点,但首先让我们简化你现有的Gremlin,因为你说它可以做你想要的:

g.V().has('user','id','338d219c-3457-4ad8-8172-37a7d897c0df').
  out('manages').
  hasLabel('client').
  out('have').
  hasLabel('site').
  out('have').
  has('job','status', 'In Progress')

请注意,这样的outE().inV()组合基本上就是这样out().事实上,如果你把它们写成outE().inV()Gremlin将会遇到重新编写遍历的麻烦,就out()在应用策略时.请参阅explain()以下两个遍历:

gremlin> g.V().outE().inV().outE().inV().explain()
==>Traversal Explanation
=============================================================================================================================================================
Original Traversal                 [GraphStep(vertex,[]), VertexStep(OUT,edge), EdgeVertexStep(IN), VertexStep(OUT,edge), EdgeVertexStep(IN)]

ConnectiveStrategy           [D]   [GraphStep(vertex,[]), VertexStep(OUT,edge), EdgeVertexStep(IN), VertexStep(OUT,edge), EdgeVertexStep(IN)]
MatchPredicateStrategy       [O]   [GraphStep(vertex,[]), VertexStep(OUT,edge), EdgeVertexStep(IN), VertexStep(OUT,edge), EdgeVertexStep(IN)]
FilterRankingStrategy        [O]   [GraphStep(vertex,[]), VertexStep(OUT,edge), EdgeVertexStep(IN), VertexStep(OUT,edge), EdgeVertexStep(IN)]
InlineFilterStrategy         [O]   [GraphStep(vertex,[]), VertexStep(OUT,edge), EdgeVertexStep(IN), VertexStep(OUT,edge), EdgeVertexStep(IN)]
IncidentToAdjacentStrategy   [O]   [GraphStep(vertex,[]), VertexStep(OUT,vertex), VertexStep(OUT,vertex)]
AdjacentToIncidentStrategy   [O]   [GraphStep(vertex,[]), VertexStep(OUT,vertex), VertexStep(OUT,vertex)]
RangeByIsCountStrategy       [O]   [GraphStep(vertex,[]), VertexStep(OUT,vertex), VertexStep(OUT,vertex)]
RepeatUnrollStrategy         [O]   [GraphStep(vertex,[]), VertexStep(OUT,vertex), VertexStep(OUT,vertex)]
PathRetractionStrategy       [O]   [GraphStep(vertex,[]), VertexStep(OUT,vertex), VertexStep(OUT,vertex)]
LazyBarrierStrategy          [O]   [GraphStep(vertex,[]), VertexStep(OUT,vertex), NoOpBarrierStep(2500), VertexStep(OUT,vertex), NoOpBarrierStep(2500)]
TinkerGraphCountStrategy     [P]   [GraphStep(vertex,[]), VertexStep(OUT,vertex), NoOpBarrierStep(2500), VertexStep(OUT,vertex), NoOpBarrierStep(2500)]
TinkerGraphStepStrategy      [P]   [TinkerGraphStep(vertex,[]), VertexStep(OUT,vertex), NoOpBarrierStep(2500), VertexStep(OUT,vertex), NoOpBarrierStep(2500)]
ProfileStrategy              [F]   [TinkerGraphStep(vertex,[]), VertexStep(OUT,vertex), NoOpBarrierStep(2500), VertexStep(OUT,vertex), NoOpBarrierStep(2500)]
StandardVerificationStrategy [V]   [TinkerGraphStep(vertex,[]), VertexStep(OUT,vertex), NoOpBarrierStep(2500), VertexStep(OUT,vertex), NoOpBarrierStep(2500)]

Final Traversal                    [TinkerGraphStep(vertex,[]), VertexStep(OUT,vertex), NoOpBarrierStep(2500), VertexStep(OUT,vertex), NoOpBarrierStep(2500)]
gremlin> g.V().out().out().explain()
==>Traversal Explanation
=============================================================================================================================================================
Original Traversal                 [GraphStep(vertex,[]), VertexStep(OUT,vertex), VertexStep(OUT,vertex)]

ConnectiveStrategy           [D]   [GraphStep(vertex,[]), VertexStep(OUT,vertex), VertexStep(OUT,vertex)]
MatchPredicateStrategy       [O]   [GraphStep(vertex,[]), VertexStep(OUT,vertex), VertexStep(OUT,vertex)]
FilterRankingStrategy        [O]   [GraphStep(vertex,[]), VertexStep(OUT,vertex), VertexStep(OUT,vertex)]
InlineFilterStrategy         [O]   [GraphStep(vertex,[]), VertexStep(OUT,vertex), VertexStep(OUT,vertex)]
IncidentToAdjacentStrategy   [O]   [GraphStep(vertex,[]), VertexStep(OUT,vertex), VertexStep(OUT,vertex)]
AdjacentToIncidentStrategy   [O]   [GraphStep(vertex,[]), VertexStep(OUT,vertex), VertexStep(OUT,vertex)]
RangeByIsCountStrategy       [O]   [GraphStep(vertex,[]), VertexStep(OUT,vertex), VertexStep(OUT,vertex)]
RepeatUnrollStrategy         [O]   [GraphStep(vertex,[]), VertexStep(OUT,vertex), VertexStep(OUT,vertex)]
PathRetractionStrategy       [O]   [GraphStep(vertex,[]), VertexStep(OUT,vertex), VertexStep(OUT,vertex)]
LazyBarrierStrategy          [O]   [GraphStep(vertex,[]), VertexStep(OUT,vertex), NoOpBarrierStep(2500), VertexStep(OUT,vertex), NoOpBarrierStep(2500)]
TinkerGraphCountStrategy     [P]   [GraphStep(vertex,[]), VertexStep(OUT,vertex), NoOpBarrierStep(2500), VertexStep(OUT,vertex), NoOpBarrierStep(2500)]
TinkerGraphStepStrategy      [P]   [TinkerGraphStep(vertex,[]), VertexStep(OUT,vertex), NoOpBarrierStep(2500), VertexStep(OUT,vertex), NoOpBarrierStep(2500)]
ProfileStrategy              [F]   [TinkerGraphStep(vertex,[]), VertexStep(OUT,vertex), NoOpBarrierStep(2500), VertexStep(OUT,vertex), NoOpBarrierStep(2500)]
StandardVerificationStrategy [V]   [TinkerGraphStep(vertex,[]), VertexStep(OUT,vertex), NoOpBarrierStep(2500), VertexStep(OUT,vertex), NoOpBarrierStep(2500)]

Final Traversal                    [TinkerGraphStep(vertex,[]), VertexStep(OUT,vertex), NoOpBarrierStep(2500), VertexStep(OUT,vertex), NoOpBarrierStep(2500)]

看看最后一行是如何相同的？在IncidentToAdjacentStrategy适用这种变化,所以最终都遍历编译为同样的事情.

在回答您的原始问题时,如果您需要拥有客户,网站和工作,请使用select():

g.V().has('user','id','338d219c-3457-4ad8-8172-37a7d897c0df').
  out('manages').
  hasLabel('client').as('c').
  out('have').
  hasLabel('site').as('s').
  out('have').
  has('job','status', 'In Progress').as('j').
  select('c','s','j')