想要 Gremlin 中同一边的两个顶点

Question

I have a graph like this

V('Producer')-E('RESPONSIBLE_PRODUCER)->V('Event')<-E('INSPECTED')-V('Engineer')
V('Event')<-E('ALIGNED_PRODUCER')-V('Producer')

That is, each 'Event' vertex has two incoming edges: one that terminates at an 'Engineer' vertex and another that terminates at a 'Producer' vertex. But the function of the Producer vertices are different depend on the edge label.

I want to get the originating Producer, the Event, Engineer and terminating Producer.

I have this gremlin code:

g.V().hasLabel('Producer').
as('responsible').
has('ProdId', 1234567).
out("RESPONSIBLE_PRODUCER").hasLabel('Event').as('event').
in("INSPECTED").hasLabel('Engineer').as('engineer').
select('responsible', 'event', 'engineer').
by(valueMap('name')).by(valueMap('name')).by(valueMap('name'))

That is, I chose a given Producer and get the Event and Engineer then return some details about each of those vertices.

I also want the Producer aligned to the Event in the same query but am not sure how to do this.

Any help is greatly appreciated.

Answer 1

You are looking for project :

g.V().has('Producer', 'ProdId', '1').as('r').
out("RESPONSIBLE_PRODUCER").hasLabel('Event').
project('responsible', 'event', 'engineer', 'aligned').
by(select('r').values('name')).
by(values('name')).
by(in('INSPECTED').values('name')).
by(in('ALIGNED_PRODUCER').values('name'))

You can see a "live" example of your problem here