在 elasticsearch 中有没有一种方法可以为前缀匹配提供比包含该单词的字符串更高的优先级？

例如，如果我搜索 ram，单词的优先级应该是这样的:

Ram Reddy
Joy Ram Das
Kiran Ram Goel
Swati Ram Goel
Ramesh Singh

我已经尝试过 here 中给出的映射. 我是这样做的:

$params = [
        "index" => $myIndex,
            "body" => [
            "settings"=> [
            "analysis"=> [
                "analyzer"=> [
                "start_with_analyzer"=> [
                    "tokenizer"=> "my_edge_ngram",
                    "filter"=> [
                    "lowercase"
                    ]
                ]
                ],
                "tokenizer"=> [
                "my_edge_ngram"=> [
                    "type"=> "edge_ngram",
                    "min_gram"=> 3,
                    "max_gram"=> 15
                ]
                ]
            ]
            ],
            "mappings"=> [
            "doc"=> [
                "properties"=> [
                "label"=> [
                    "type"=> "text",
                    "fields"=> [
                    "keyword"=> [
                        "type"=> "keyword"
                    ],
                    "ngramed"=> [
                        "type"=> "text",
                        "analyzer"=> "start_with_analyzer"
                    ]
                    ]
                ]
                ]
            ]
            ]
    ]
    ];
    $response = $client->indices()->create($params);    // create an index

并像这样搜索:

$body = [
        "size" => 100,

        '_source' => $select,
        "query"=> [
            "bool"=> [
              "should"=> [
                [
                  "query_string"=> [
                    "query"=> "ram*",
                    "fields"=> [
                      "value"
                    ],
                    "boost"=> 5
                  ]
                ],
                [
                  "query_string"=> [
                    "query"=> "ram*",
                    "fields"=> [
                      "value.ngramed"
                    ],
                    "analyzer"=> "start_with_analyzer",
                    "boost"=> 2
                  ]
                ]
              ],
              "minimum_should_match"=> 1
            ]
          ]
    ];

$params = [
    'index' => $myIndex,
    'type' => $myType,
    'body' => []
];
$params['body'] = $body;
$response = $client->search($params);

查询的json如下:

    {
  "size": 100,
  "_source": [
    "label",
    "value",
    "type",
    "sr"
  ],
  "query": {
    "bool": {
      "should": [
        {
          "query_string": {
            "query": "ram*",
            "fields": [
              "value"
            ],
            "boost": 5
          }
        },
        {
          "query_string": {
            "query": "ram*",
            "fields": [
              "value.ngramed"
            ],
            "analyzer": "start_with_analyzer",
            "boost": 2
          }
        }
      ],
      "minimum_should_match": 1,
      "must_not": {
        "match_phrase": {
          "type": "propertyValue"
        }
      }
    }
  }
}

我正在使用 elasticsearch 5.3.2 有没有其他方法可以使用php中的搜索方法对关系数据库中的搜索结果进行排序？

最佳答案

除非确实需要，否则不应启用 fielddata。为了克服这个问题，您可以使用子字段。 对您的代码进行以下更改:

                       "label"=>[
                            "type"=>"text",
                            //"fielddata"=> true, ---->remove/comment this line
                            "analyzer"=>"whitespace",
                            "fields"=>[
                                "keyword"=>[
                                    "type"=>"keyword"
                                ]
                            ]
                        ]

要按type 字段排序，请改用type.keyword。此更改适用于 text 类型的任何字段，并且有可用的 keyword 类型的子字段(假设此字段的名称是 keyword) .所以改变如下:

'sort' => [
    ["type.keyword"=>["order"=>"asc"]],
    ["sr"=>["order"=>"asc"]],
    ["propLabels"=>["order"=>"asc"]],
    ["value"=>["order"=>"asc"]]
]

更新:索引创建和查询以获得所需的输出

创建索引如下:

{
  "settings": {
    "analysis": {
      "analyzer": {
        "start_with_analyzer": {
          "tokenizer": "my_edge_ngram",
          "filter": [
            "lowercase"
          ]
        }
      },
      "tokenizer": {
        "my_edge_ngram": {
          "type": "edge_ngram",
          "min_gram": 3,
          "max_gram": 15
        }
      }
    }
  },
  "mappings": {
    "_doc": {
      "properties": {
        "name": {
          "type": "text",
          "fields": {
            "keyword": {
              "type": "keyword"
            },
            "ngramed": {
              "type": "text"
            }
          }
        }
      }
    }
  }
}

使用下面的查询得到想要的结果:

{
  "query": {
    "bool": {
      "should": [
        {
          "query_string": {
            "query": "Ram",
            "fields": [
              "name"
            ],
            "boost": 5
          }
        },
        {
          "query_string": {
            "query": "Ram",
            "fields": [
              "name.ngramed"
            ],
            "analyzer": "start_with_analyzer",
            "boost": 2
          }
        }
      ],
      "minimum_should_match": 1
    }
  }
}

在上面，提升值为 5 的查询增加了 name 中存在 Ram 的那些文档的分数。另一个使用 boost 2 的查询进一步提高了 name 以 Ram 开头的文档的分数。

示例 O/P:

"hits": [
  {
    "_index": "test",
    "_type": "_doc",
    "_id": "2",
    "_score": 2.0137746,
    "_source": {
      "name": "Ram Reddy"
    }
  },
  {
    "_index": "test",
    "_type": "_doc",
    "_id": "1",
    "_score": 1.4384104,
    "_source": {
      "name": "Joy Ram Das"
    }
  },
  {
    "_index": "test",
    "_type": "_doc",
    "_id": "3",
    "_score": 0.5753642,
    "_source": {
      "name": "Ramesh Singh"
    }
  }
]

关于php - 在php中的elasticsearch中优先考虑前缀匹配，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/56271849/