Enterprise test> db.foo.aggregate([ { "$match": { "$and": [{ "a": 1 }, { "$or": [{ "b": "x" }, { "c": "y" }] }] } }]);
MongoServerError[Location9768403]: FetchNode must have direct or indirect children that somehow filter data.

winningPlan: {
      isCached: false,
      stage: 'FETCH',
      filter: {
        '$and': [
          { a: { '$eq': 1 } },
          {
            '$or': [ { b: { '$eq': 'x' } }, { c: { '$eq': 'y' } } ]
          }
        ]
      },
      inputStage: {
        stage: 'AND_HASH',
        inputStages: [
          {
            stage: 'IXSCAN',
            keyPattern: { a: 1 },
            indexName: 'a_1',
            isMultiKey: false,
            multiKeyPaths: { a: [] },
            isUnique: false,
            isSparse: false,
            isPartial: false,
            indexVersion: 2,
            direction: 'forward',
            indexBounds: { a: [ '[1, 1]' ] }
          },
          {
            stage: 'OR',
            inputStages: [
              {
                stage: 'IXSCAN',
                keyPattern: { b: 1 },
                indexName: 'b_1',
                isMultiKey: false,
                multiKeyPaths: { b: [] },
                isUnique: false,
                isSparse: false,
                isPartial: false,
                indexVersion: 2,
                direction: 'forward',
                indexBounds: { b: [ '["x", "x"]' ] }
              },
              {
                stage: 'IXSCAN',
                keyPattern: { c: 1 },
                indexName: 'c_1',
                isMultiKey: false,
                multiKeyPaths: { c: [] },
                isUnique: false,
                isSparse: false,
                isPartial: false,
                indexVersion: 2,
                direction: 'forward',
                indexBounds: { c: [ '["y", "y"]' ] }
              }
            ]
          }
        ]
      }
    },