Crawling the Relationships, In Reverse

You can also crawl the graph in reverse. Although there is no predicate that begins with actor/ that references a subject in credit collection, we know that actors are referenced in the credit collection.

In order to select all of the credits that belong to an actor, like- for instance ["actor/name", "Tilda Swinton"], we can

{
    "select": ["*", {"credit/_actor": ["*"]}],
    "from": ["actor/name", "Tilda Swinton"]
}

Notice that, we use the relevant predicate name, credit/actor, but because we are crawling the graph in reverse, we add an, _ in front of actor. We don't switch the order of the original predicate (actor/credit or actor/_credit are both wrong!), but we do need to add the _.

The results will mirror the shape of our query, and use the credit/_actor name in showing us our results:

{
  "status": 200,
  "result": {
    "credit/_actor": [
      {
        "credit/id": "52fe43cdc3a36847f8070be5",
        "credit/character": "Karen Crowder",
        "credit/order": 2,
        "credit/actor": {
          "_id": 4316442133756
        },
        "_id": 4312147268629
      },
      ...
    ],
    "actor/id": 3063,
    "actor/name": "Tilda Swinton",
    "actor/gender": 1,
    "_id": 4316442133756
  },
  "fuel": 94,
  "block": 3373,
  "time": "188.42ms"
}

Crawl the Graph in Reverse to Get Movie Information.

The movie collection has a predicate, `movie/productionCompanies`.

Can you select all predicates from the `productionCompany` collection and crawl the graph, in reverse, to get all predicates from each movie?

Remember, we never switch the order of the original predicate.