FaunaDB index query returning empty array... any Ideas?

Question

I'm running this query:

Paginate(
    Match(
        Index("chatMemberships_by_user"), 
        Ref(Collection('users'), "307731780020994112")
    )
)

On this index:

{
  name: "chatMemberships_by_user",
  serialized: true,
  source: "chats",
  terms: [
    {
      field: ["data", "user"]
    }
  ],
  values: [
    {
      field: ["data", "lastActive"]
    },
    {
      field: ["data", "chat"]
    },
    {
      field: ["ref"]
    }
  ]
}

The chatMemberships collection contains these two documents:

{
  "ref": Ref(Collection("chatMemberships"), "307917574923878464"),
  "ts": 1629911932790000,
  "data": {
    "user": Ref(Collection("users"), "307731780020994112"),
    "chat": Ref(Collection("chats"), "307917574915489856"),
    "createdAt": Time("2021-08-25T17:18:52.711023Z"),
    "lastActive": Time("2021-08-25T17:18:52.711023Z")
  }
},
{
  "ref": Ref(Collection("chatMemberships"), "307917574923879488"),
  "ts": 1629911932790000,
  "data": {
    "user": Ref(Collection("users"), "307828268328812611"),
    "chat": Ref(Collection("chats"), "307917574915489856"),
    "createdAt": Time("2021-08-25T17:18:52.711023Z"),
    "lastActive": Time("2021-08-25T17:18:52.711023Z")
  }
}

After running the query, the result I get is an empty array instead of an array containing the matching chatMembership document (should be the first one in the screenshot).

{ data: [] }

Any idea on what's causing this? Am I crazy or is this a bug? Thanks!

Answer 1

The problem was that I was referencing the wrong source collection in the index. It should have been “chatMemberships” instead of “chats”.