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Elasticsearch - search for multiple values in a list of nested values


I'm trying to get the the documents that match all the itens inside a list, the field that I'm searching for is inside a list of nested :

map of my index:

PUT testindex1
{
  "mappings": {
    "properties": {
    "patients": {
      "type": "nested",
      "properties": {
        "name": {
          "type": "keyword"
        },
        "age": {
          "type": "keyword"
        }
      }
    }
  }
  }
}

Documents

PUT testindex1/_doc/1
{ 
  "patients": [ 
    {"name" : "1", "age" : "1"},
    {"name" : "1", "age" : "2"},
    {"name" : "1", "age" : "3"}
  ] 
}

PUT testindex1/_doc/2
{ 
  "patients": [ 
    {"name" : "1", "age" : "1"},
    {"name" : "1", "age" : "2"},
    {"name" : "1", "age" : "3"}
  ] 
}

PUT testindex1/_doc/3
{ 
  "patients":[ 
    {"name" : "1", "age" : "2"},
    {"name" : "1", "age" : "5"},
    {"name" : "1", "age" : "4"}
  ] 
}

what I'm trying to get is all the documents where the patients ages are inside have list ["2", "1"], in this case only the document 1 and 2. I know that i can update the map by using this approach

But this would mean that I would have to reprocess the entire dataset

get patients that have both ages "1" and "2" (only patients of index 1 and 2)


Solution

  • I've found the answer here : Search a nested field for multiple values on the same field with elasticsearch

    Basicaly you need to search via a nested must :

    GET testindex1/_search
    {
      "query": {
        "bool": {
          "filter": [
            {
              "nested": {
                "path": "patients",
                "query": {
                  "bool": {
                    "filter": [
                      {
                        "match": {
                          "patients.age": "2"
                        }
                      }
                    ]
                  }
                }
              }
            },
            {
              "nested": {
                "path": "patients",
                "query": {
                  "bool": {
                    "filter": [
                      {
                        "match": {
                          "patients.age": "1"
                        }
                      }
                    ]
                  }
                }
              }
            }
          ]
        }
      }
    }
    

    This returns only the patients that have age 1 and age 2, returning the following output :

    {
      "took" : 1,
      "timed_out" : false,
      "_shards" : {
        "total" : 1,
        "successful" : 1,
        "skipped" : 0,
        "failed" : 0
      },
      "hits" : {
        "total" : {
          "value" : 2,
          "relation" : "eq"
        },
        "max_score" : 0.0,
        "hits" : [
          {
            "_index" : "testindex1",
            "_id" : "1",
            "_score" : 0.0,
            "_source" : {
              "patients" : [
                {
                  "name" : "1",
                  "age" : "1"
                },
                {
                  "name" : "1",
                  "age" : "2"
                },
                {
                  "name" : "1",
                  "age" : "3"
                }
              ]
            }
          },
          {
            "_index" : "testindex1",
            "_id" : "2",
            "_score" : 0.0,
            "_source" : {
              "patients" : [
                {
                  "name" : "1",
                  "age" : "1"
                },
                {
                  "name" : "1",
                  "age" : "2"
                },
                {
                  "name" : "1",
                  "age" : "3"
                }
              ]
            }
          }
        ]
      }
    }