Inner Hits and Rescoring

[ravensedge]

Hi all,

I have the following problem: I want to do filtering on a nested field, then rescore based on the fields that matched the filter.

In the minimum working example below, the query returns a score of 9000. However, I would like it to only return 5 as 5 is the only inner value that matches the initial query of < 70.

PUT testing_index
{
  "mappings": {
    "doc": {
      "properties": {
        "inner": {
          "type": "nested"
        }
      }
    }
  }
}

PUT testing_index/doc/1
{
  "value": 3,
  "inner": [
    {
      "inner_value": 5
    },
    {
      "inner_value": 9000
    }
  ]
}

GET testing_index/_search
{
  "query": {
    "nested": {
      "path": "inner",
      "query": {
        "range": {
          "inner.inner_value": {
            "lt": 70
          }
        }
      }
    }
  },
  "rescore": {
    "query": {
      "rescore_query": {
        "nested": {
          "path": "inner",
          "query": {
            "function_score": {
              "field_value_factor": {
                "field": "inner.inner_value"
              }
            }
          },
          "score_mode": "max"
        }
      },
      "query_weight": 0,
      "rescore_query_weight": 1
    }
  }
}

The rescore is absolutely necessary. In my use case, there are billions of documents and the rescoring function is expensive. This means I have to write an initial function score, take the top 10000 or so candidates and then run the rescore.

Thanks!