具有不同权重的多字段 Elasticsearch 补全建议器

Question

我在 Elasticsearch 中使用 Completion Suggester 来允许部分单词匹配查询。在我的索引 (products_index) 中，我希望能够同时查询 product_name 字段和 brand 字段。这是我的映射:

POST /product_index

mappings: {
  products: {
    properties: {
      brand: {
        type: "string",
        analyzer: "english"
      },
      product_name: {
        type: "string",
        analyzer: "english"
      },
      id: {
        type: "long"
      },
      lookup_count: {
        type: "long"
      },
      suggest: {
        type: "completion",
        analyzer: "simple",
        payloads: true,
        preserve_separators: true,
        preserve_position_increments: true,
        max_input_length: 50
      },
      upc: {
        type: "string"
      }
    }
  }
}

这是我的数据:

POST /product_index/products/2
{
  id: 2,
  brand: "Coca-Cola",
  product_name: "Classic Coke",
  suggest: {
    input: [
      "Classic Coke",
      "Coca-Cola"
    ],
    output: "Classic Coke - Coca-Cola",
    payload: {
      id: 2,
      product_name: "Classic Coke",
      brand: "Coca-Cola",
      popularity: 10
    },
    weight: 0
  }
}

这是我的查询:

POST /product_index/_search

"suggest": {
  "product_suggest": {
    "text": 'coca-co',
    "completion": {
      "field": 'suggest'
    }
  }
}

除了我想为 product_name 字段提供比 brand 字段更高的权重外，这非常有效。有什么办法可以做到这一点？我调查了这个article关于使用 bool 查询，但我对 Elasticsearch 很陌生，不确定如何在完成建议的情况下应用它。

非常感谢!

Answer 1

正如 redox 所说，完成建议器非常简单，不支持条目提升。我的解决方案是制作两个建议字段，一个用于品牌，一个用于产品名称:

POST /product_index
{
  "mappings": {
    "products": {
      "properties": {
        "brand": {
          "type": "string",
          "analyzer": "english"
        },
        "product_name": {
          "type": "string",
          "analyzer": "english"
        },
        "id": {
          "type": "long"
        },
        "lookup_count": {
          "type": "long"
        },
        "product-suggest": {
          "type": "completion",
          "analyzer": "simple",
          "payloads": true,
          "preserve_separators": true,
          "preserve_position_increments": true,
          "max_input_length": 50
        },
        "brand-suggest": {
          "type": "completion",
          "analyzer": "simple",
          "payloads": true,
          "preserve_separators": true,
          "preserve_position_increments": true,
          "max_input_length": 50
        },
        "upc": {
          "type": "string"
        }
      }
    }
  }
}

索引时，填写两个字段:

POST /product_index/products/2
{
  "id": 2,
  "brand": "Coca-Cola",
  "product_name": "Classic Coke",
  "brand-suggest": {
    "input": [
      "Coca-Cola"
    ],
    "output": "Classic Coke - Coca-Cola",
    "payload": {
      "id": 2,
      "product_name": "Classic Coke",
      "brand": "Coca-Cola",
      "popularity": 10
    }
  },
  "product-suggest": {
    "input": [
      "Classic Coke"
    ],
    "output": "Classic Coke - Coca-Cola",
    "payload": {
      "id": 2,
      "product_name": "Classic Coke",
      "brand": "Coca-Cola",
      "popularity": 10
    }
  }
}

查询时，在品牌和产品建议者上提出一个建议:

POST /product_index/_search
{
    "suggest": {
      "product_suggestion": {
        "text": "coca-co",
        "completion": {
          "field": "product-suggest"
        }
      },
      "brand_suggestion": {
        "text": "coca-co",
        "completion": {
          "field": "brand-suggest"
        }
      }
    }
}

您可以将品牌建议的建议列表附加到产品建议的建议列表中，去除重复后，得到只有相关建议、没有重复和产品建议在前的建议列表。

另一种解决方案是使用提升品牌和产品的查询，而不是使用建议器。但是，此实现速度较慢，因为它不使用建议器。