弹性搜索 - 默认文档

Question

I have 3 documents in my index

document 1:

x: 1

document 2:

x: 1 y: 1

document 3:

x: 2 y: 3

I am using this query to find relevant documents

"query" : {
        "bool" : {
            "should" : [

                {
                    "match" : {
                        "X" : {
                            "query" : 1,
                            "boost" : 500
                        }
                    }
                },{
                    "match" : {
                       "Y" : 5
                    }
                }
            ]
        }
    }

this query works as I expect when I look for x:1, y:1 I get DOC2 with a highest score.

what I try to achieve: when the query is x:1, y:5 I want to get the DOC1 (as default). is it possible?

I know that I can achieve it by adding queries 'AND NOT EXISTS'. is there another way?

Answer 1

How about forcing the x and making y voluntary, ie:

GET xy/_search
{
  "query": {
    "bool": {
      "must": [
        {
          "match": {
            "x": {
              "query": 1,
              "boost": 500
            }
          }
        }
      ],
      "should": [
        {
          "match": {
            "y": 5
          }
        }
      ]
    }
  }
}

Answer 2

How about simply playing with bool statements?

It makes you selecting the doc 1 (default), and if you find the correct value of Y, you boost the score if the value exists. ie:

{
  "query": {
    "bool": {
      "should": [
        {
          "bool": {
              "must" : [
                  {
                    "match" : {
                        "x" : {
                            "query" : 1,
                            "boost" : 500
                        }
                    }
                },
                {
                    "bool" : 
                    {
                        "must_not" : {
                            "exists" : {
                            "field": "y"
                            }
                        }
                    }    
                }

                ]
          }
        },
        {
            "bool": {
              "must" : [
                  {
                    "match" : {
                        "x" : {
                            "query" : 1
                        }
                    }
                },
                {
                    "match" : {
                        "y" : {
                            "query" : 5,
                            "boost" : 600
                        }
                    }
                }
            ]
          }
        }
      ]
    }
  }
}

Also you can use function_score statement:

{   
    "query" : {
        "function_score": {
            "query" : {
                "bool" : {
                    "should" : [

                        {
                            "match" : {
                                "x" : {
                                    "query" : 1,
                                    "boost": 10
                                }
                            }
                        },{
                            "match" : {
                               "y" :  {
                                   "query": 5,
                                   "boost": 20
                               }
                            }
                        }
                    ]
                }
            },
            "functions": [
              {
                  "filter": { "match": { "x": "1" } },
                  "weight": 1
              },
              {
                  "filter":  {"bool": {"must": { "match": { "y": "5" } } } },
                  "weight": 10
              },
              {
                  "filter":  {"bool": {"must_not": { "exists": { "field": "y" } } } },
                  "weight": 1
              }
            ],
            "score_mode": "sum",
            "boost_mode": "sum"
        }
    }
}