nosql - Elasticsearch - 标记强度(嵌套/子文档增强)

Question

给出具有标签集合的帖子的流行示例，假设我们希望每个标签不仅仅是一个字符串，而是一个字符串元组和一个表示所述标签强度的 double 。

一个查询如何根据标签强度的总和来发布和评分(假设我们正在搜索标签名称中的确切术语)

Answer 1

可以通过将标签索引为 nested documents 来完成然后使用 nested结合 custom score 进行查询询问。在下面的示例中，术语查询找到匹配的标签，自定义分数查询使用“标签”文档的“wight”字段的值作为分数，嵌套查询使用这些分数的总和作为顶级文档的最终分数.

curl -XDELETE 'http://localhost:9200/test-idx'
echo
curl -XPUT 'http://localhost:9200/test-idx' -d '{
    "mappings": {
        "doc": {
            "properties": {
                "title": { "type": "string" },
                "tags": {
                    "type": "nested",
                    "properties": {
                        "tag": { "type": "string", "index": "not_analyzed" },
                        "weight": { "type": "float" }
                    }
                }
            }
        }
    }
}'
echo
curl -XPUT 'http://localhost:9200/test-idx/doc/1' -d '{
    "title": "1",
    "tags": [{
        "tag": "A",
        "weight": 1
    }, {
        "tag": "B",
        "weight": 2
    }, {
        "tag": "C",
        "weight": 4
    }]
}
'
echo
curl -XPUT 'http://localhost:9200/test-idx/doc/2' -d '{
    "title": "2",
    "tags": [{
        "tag": "B",
        "weight": 2
    }, {
        "tag": "C",
        "weight": 3
    }]
}
'
echo
curl -XPUT 'http://localhost:9200/test-idx/doc/3' -d '{
    "title": "3",
    "tags": [{
        "tag": "B",
        "weight": 2
    }, {
        "tag": "D",
        "weight": 4
    }]
}
'
echo
curl -XPOST 'http://localhost:9200/test-idx/_refresh'
echo
# Example with custom script (slower but more flexable)
curl -XGET 'http://localhost:9200/test-idx/doc/_search?pretty=true' -d '{
    "query" : { 
        "nested": {
            "path": "tags",
            "score_mode": "total",
            "query": {
                "custom_score": {
                    "query": {
                        "terms": {
                            "tag": ["A", "B", "D"],
                            "minimum_match" : 1
                        }
                    },
                    "script" : "doc['\''weight'\''].value"
                }
            }
        }
    },
    "fields": []
}'
echo