Terms Set Query

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The terms_set query is a new query and its syntax may change in the future

Returns any documents that match with at least one or more of the provided terms. The terms are not analyzed and thus must match exactly. The number of terms that must match varies per document and is either controlled by a minimum should match field or computed per document in a minimum should match script.

The field that controls the number of required terms that must match must be a number field:

PUT /my-index
{
    "mappings": {
        "_doc": {
            "properties": {
                "required_matches": {
                    "type": "long"
                }
            }
        }
    }
}

PUT /my-index/_doc/1?refresh
{
    "codes": ["ghi", "jkl"],
    "required_matches": 2
}

PUT /my-index/_doc/2?refresh
{
    "codes": ["def", "ghi"],
    "required_matches": 2
}

An example that uses the minimum should match field:

GET /my-index/_search
{
    "query": {
        "terms_set": {
            "codes" : {
                "terms" : ["abc", "def", "ghi"],
                "minimum_should_match_field": "required_matches"
            }
        }
    }
}

Response:

{
  "took": 13,
  "timed_out": false,
  "_shards": {
    "total": 5,
    "successful": 5,
    "skipped" : 0,
    "failed": 0
  },
  "hits": {
    "total": 1,
    "max_score": 0.5753642,
    "hits": [
      {
        "_index": "my-index",
        "_type": "_doc",
        "_id": "2",
        "_score": 0.5753642,
        "_source": {
          "codes": ["def", "ghi"],
          "required_matches": 2
        }
      }
    ]
  }
}

Scripts can also be used to control how many terms are required to match in a more dynamic way. For example a create date or a popularity field can be used as basis for the number of required terms to match.

Also the params.num_terms parameter is available in the script to indicate the number of terms that have been specified.

An example that always limits the number of required terms to match to never become larger than the number of terms specified:

GET /my-index/_search
{
    "query": {
        "terms_set": {
            "codes" : {
                "terms" : ["abc", "def", "ghi"],
                "minimum_should_match_script": {
                   "source": "Math.min(params.num_terms, doc['required_matches'].value)"
                }
            }
        }
    }
}