neuxregime
neuxregime
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ATApache TinkerPop
Created by neuxregime on 6/20/2023 in #questions
indexOf Vertex with given property in a sorted list
Hi all! I've been trying to create a paginated GET REST api and sometimes I need to enforce a range on the resulting vertices starting from a vertex matching a given ID. Let's say my gremlin query so far returns the following list of vertices, sorted based on some property comparison: 
[
  V{id:Z}
  V{id:F}
  V{id:K}
  V{id:A}
  V{id:N}
  V{id:T}
  V{id:C}
]
[
  V{id:Z}
  V{id:F}
  V{id:K}
  V{id:A}
  V{id:N}
  V{id:T}
  V{id:C}
]
Is there a way of asking gremlin what is the index of vertex with id K in the above list? Can all of this be done in a single query so that my final result simply returns the following, given K and a range of 3? 
[
  V{id:K}
  V{id:A}
  V{id:N}
]
[
  V{id:K}
  V{id:A}
  V{id:N}
]
Some pseudocode for clarity: 
g.V()
.hasLabel("profile")
.order()
.by("date", gremlin.process.order.asc);   // at this point we have the whole list
.range(indexOf(id=K), indexOf(id=K) + 3)  // this is the hiccup,
                                          // how to find indexOf(id=K) in the sorted result
.toList()
g.V()
.hasLabel("profile")
.order()
.by("date", gremlin.process.order.asc);   // at this point we have the whole list
.range(indexOf(id=K), indexOf(id=K) + 3)  // this is the hiccup,
                                          // how to find indexOf(id=K) in the sorted result
.toList()
Thank you in advance
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