Traversing a Linked List Structure with @normalize and @recurse

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Hello,

I have a linked list structure that I want to traverse. I was able to use recurse to go through the entire list which worked like a charm, but I want to see if it’s possible to normalize the data so that it isn’t so deeply nested.

Here is the basic schema for the structure. The Event type has a nextEvent predicate on it that points to another node of type Event.

<Event.nextEvent>: uid .
<Event.type>: string .

type <Event> {
	Event.type
	Event.nextEvent
}

I was able to use recurse to query the list like so

{
  test(func: uid(0x274b)) @recurse {
    uid
    Event.type
    Event.nextEvent
  }
}

And the response

"data": {
    "test": [
      {
        "uid": "0x274b",
        "Event.type": "Test Event",
        "Event.nextEvent": {
          "uid": "0x274d",
          "Event.type": "Test Event",
          "Event.nextEvent": {
            "uid": "0x274e",
            "Event.type": "Test Event",
            "Event.nextEvent": {
              "uid": "0x274f",
              "Event.type": "Hello Event"
            }
          }
        }
      }
    ]
  }

Is there anyway to flatten this data so that it isn’t so deeply nested? I tried using @normalize but I’m struggling to get the results I want which would look something like an array with the nodes.

Thanks in advance!

2

Hello @djhertel

In order to use @normalize you need to use an alias:

{
  test(func: uid(0x274b)) @recurse @normalize {
    uid
    type: Event.type # this is alias
    Event.nextEvent
  }
}

The response will be something like this:

 "data": {
    "test": [
      {
        "type": [
          "Test Event",
          "Test Event",
          "Test Event",
          "Hello Event"
        ]
      }
    ]
  },
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