c# - Elastic Search 5.x 嵌套多个查询 C#

Question

我将 C# 与那些 nuget 包一起使用；

  <package id="Elasticsearch.Net" version="5.2.0" targetFramework="net462" />
  <package id="NEST" version="5.2.0" targetFramework="net462" />
  <package id="Newtonsoft.Json" version="9.0.1" targetFramework="net462" />

我想在这里做什么，我想获得价格范围为 2000 - 3000 的“白色”商品。这是一个简单的搜索 API 请求，对吗？

所以我为此写了一段代码。这里是;

private static void Search(IElasticContext elasticContext, string indexName)
    {
        IQueryContainer termQueryContainer = new QueryContainer();
        termQueryContainer.Term = new TermQuery
                                  {
                                      Field = new Field("description"),
                                      Value = "white"
                                  };

        IQueryContainer rangeQueryContainer = new QueryContainer();
        rangeQueryContainer.Range = new NumericRangeQuery
                                    {
                                        Field = new Field("price"),
                                        LessThanOrEqualTo = 3000,
                                        GreaterThanOrEqualTo = 2000
                                    };

        //Should get 2 items.

        SearchRequest<Product> searchRequest = new SearchRequest<Product>(indexName, typeof(Product))
                                               {
                                                   Size = 10,
                                                   From = 0,
                                                   Query = (QueryContainer) rangeQueryContainer,
                                                   PostFilter = (QueryContainer) termQueryContainer
                                               };

        EsSearchResponse<Product> response = elasticContext.Search<Product>(searchRequest);

        Console.WriteLine(response.StatusMessage);

        if (response.IsValid)
        {
            foreach (Product product in response.Documents)
            {
                Console.WriteLine("Id: {0} | Name: {1}", product.Id, product.Name);
            }
        }
    }

但它不起作用，因为请求已成功但结果中没有文档，但我有。我可以使用 Sense 插件查看文档。

如果我组合两个查询，nest 将在运行时抛出异常(说:“QueryContainer can only hold a single query already contains a TermQuery”)。这里是;

此外，我不能使用流畅的 api，因为我将参数传递给了我的类似存储库的函数；

    EsSearchResponse<Product> response = elasticContext.Search<Product>(searchRequest);

如何在 Nest dll 的 SearchRequest 中组合两个简单的查询(在描述字段中搜索和价格范围在 2000-3000 之间)。我做错了什么？

Answer 1

您要做的是从两个查询中形成一个复合查询，其中两个查询都必须由文档满足才能被视为匹配项。 A bool query is used to combine queries in this manner , 使用 must必须满足指定两个查询的子句。这是一个示例，使用对象初始化语法

var client = new ElasticClient();
var indexName = "index-name";
var mustClauses = new List<QueryContainer>();

mustClauses.Add(new TermQuery
{
    Field = new Field("description"),
    Value = "white"
});

mustClauses.Add(new NumericRangeQuery
{
    Field = new Field("price"),
    LessThanOrEqualTo = 3000,
    GreaterThanOrEqualTo = 2000
});

var searchRequest = new SearchRequest<Product>(indexName)
{
    Size = 10,
    From = 0,
    Query = new BoolQuery { Must = mustClauses }
};

var searchResponse = client.Search<Product>(searchRequest);

随着 range查询，文档要么匹配查询子句，要么不匹配，因此我们可以通过将其添加为 bool 来放弃为查询计算的分数。查询 filter子句

var indexName = "index-name";
var mustClauses = new List<QueryContainer>();
var filterClauses = new List<QueryContainer>();

mustClauses.Add(new TermQuery
{
    Field = new Field("description"),
    Value = "white"
});

filterClauses.Add(new NumericRangeQuery
{
    Field = new Field("price"),
    LessThanOrEqualTo = 3000,
    GreaterThanOrEqualTo = 2000
});

var searchRequest = new SearchRequest<Product>(indexName)
{
    Size = 10,
    From = 0,
    Query = new BoolQuery 
    { 
        Must = mustClauses,
        Filter = filterClauses
    }
};

var searchResponse = client.Search<Product>(searchRequest);