Gremlin 反向遍历

Question

In a Gremlin graphdb I have something like:

root
   level1
      level2
        levelN

If I know 'root' I can find 'levelN' using the following query:

g.v().has('name','root').repeat(out().simplePath()).until(has('name','levelN'))

but how do I go the other way, given I know 'levelN', how do I find 'root' it doesn't seem to be possible to do:

g.v().has('name','levelN').repeat(in().simplePath()).until(has('name','root'))

TIA

/Søren

Answer 1

Depending on the client language you are using, in is a reserved word and should be written as __.in() or in_() .

Check Vertex Steps in the TinkerPop documentation for more information: http://tinkerpop.apache.org/docs/current/reference/#vertex-steps