Elasticsearch: combine match_phrase and match in order to get only results for match_phrase (if any)

Question

I have an index of books where I store the full text content of books (with stopwords removed, but that's not important for my question). I have the following query:

> GET /books/_search
>     {
>       "_source": {
>           "includes": ["author", "title"]
>       },
>       "query": {
>         "bool": {
>           "should": [
>             {
>               "match_phrase": {
>                 "body": "all happy families are alike"
>               }
>             },
>             {
>               "match": {
>                 "body": "all happy families are alike"
>               }
>             }
>           ]
>         }
>       }
>     }

I get matches for all documents that have the full string with highest score and then, with lower scores, those having one or more of matching terms: first match is 'Anna Karenina' with very high score, then any book that has 'happy' , 'families' in it. What I would like to obtain:

1. if a document matches with condition "match_phrase", then get ONLY this result (i.e. get ONLY Anna Karenina, discard the rest)
2. else, list all matching documents with descending score (expected behaviour)

I struggle to find how to get point 1.

Answer 1

Exact and partial matches cannot be returned conditionally. You can use named queries to check at client side if match is exact/partial.

GET books/_search
{
  "query": {
    "bool": {
      "should": [
        {
          "match_phrase": {
            "body": {
              "query": "all happy families are alike",
              "_name":"exact_match"    ---> name of query(can be anything)
            }
          }
        },
        {
          "match": {
            "body":  {
              "query": "all happy families are alike",
              "_name":"partial_match"
            }
          }
        }
      ]
    }
  }
}

Result:

"hits" : [
      {
        "_index" : "books",
        "_type" : "_doc",
        "_id" : "4i0MeG0BCVIM-bi3Fif1",
        "_score" : 4.1589947,
        "_source" : {
          "title" : "Anna Karenina",
          "body" : "all happy families are alike"
        },
        "matched_queries" : [   ---> returns name of queries where condition matched
          "exact_match",
          "partial_match"
        ]
      },
      {
        "_index" : "books",
        "_type" : "_doc",
        "_id" : "4y0MeG0BCVIM-bi3aScM",
        "_score" : 0.44216567,
        "_source" : {
          "title" : "book 1",
          "body" : "happy alike"
        },
        "matched_queries" : [  ---> returns name of queries where condition matched
          "partial_match"
        ]
      }
    ]
  }