NEST带有多个术语的条件筛选器查询

时间:2016-06-08 09:00:06

标签: c# elasticsearch nest

我想像这样做一个ElasticSearch查询:

{
    "query" :
    {
        "bool" :
        {
            "filter" : [
                {
                    "terms" :
                    {
                        "name" : ["name1", "name2"]
                    }
                },
                {
                    "terms" :
                    {
                        "color" : ["orange", "red"]
                    }
                }
            ]
        }
    }
}

我试图在NEST中实现它,如下所示:

_elasticClient
    .SearchAsync<MyDocument>(s =>
        s.Index("myindex")
            .Query(q => q
                .Bool(bq => bq
                    .Filter(fq =>
                    {
                        QueryContainer query = null;

                        if (nameList.Any()) {
                            query &= fq.Terms(t => t.Field(f => f.Name).Terms(nameList));
                        }

                        if (colorList.Any()) {
                            query &= fq.Terms(t => t.Field(f => f.Color).Terms(colorList));
                        }

                        return query;
                    })
                )
            )
    );

但是这给了我一个这样的查询,其中过滤器包含在 bool必须中:

{
    "query" :
    {
        "bool" :
        {
            "filter" : [
                {
                    "bool" :
                    {
                        "must" : [
                            {
                                "terms" :
                                {
                                    "name" : ["name1", "name2"]
                                }
                            },
                            {
                                "terms" :
                                {
                                    "color" : ["orange", "red"]
                                }
                            }
                        ]
                    }
                }
            ]
        }
    }
}

我应该如何更改NEST代码以便为我提供正确的查询?是否必须将我的术语添加到 QueryContainer 之外的其他内容中?

3 个答案:

答案 0 :(得分:18)

如果要检查条件过滤器,可以在进行查询之前创建过滤器列表,如下所示:

var nameList = new[] {"a", "b"};
var colorList = new[] {1, 2};

var filters = new List<Func<QueryContainerDescriptor<MyDocument>, QueryContainer>>();
if (nameList.Any())
{
     filters.Add(fq=> fq.Terms(t => t.Field(f => f.Name).Terms(nameList)));
}

if (colorList.Any())
{
    filters.Add(fq => fq.Terms(t => t.Field(f => f.Color).Terms(colorList)));
}

ISearchResponse<Property> searchResponse =
     elasticClient.Search<MyDocument>(x => x.Query(q => q
     .Bool(bq => bq.Filter(filters))));

如果您在进行过滤查询之前不需要检查任何条件,那么您可以拥有类似的内容:

ISearchResponse<MyDocument> searchResponse =
elasticClient.Search<MyDocument>(x => x.Query(q => q
.Bool(bq => bq
.Filter(
        fq => fq.Terms(t => t.Field(f => f.Name).Terms(nameList)),
        fq => fq.Terms(t => t.Field(f => f.Color).Terms(colorList))
        ))));

答案 1 :(得分:11)

bool查询的Filter方法需要params Func<QueryContainerDescriptor<T>, QueryContainer>[],以便您可以将多个表达式传递给多个过滤器

var nameList = new string[] { "name1", "name2" };
var colorList = new string[] { "orange", "red" };

client.SearchAsync<MyDocument>(s => s
        .Index("myindex")
        .Query(q => q
            .Bool(bq => bq
                .Filter(
                    fq => fq.Terms(t => t.Field(f => f.Name).Terms(nameList)),
                    fq => fq.Terms(t => t.Field(f => f.Color).Terms(colorList))
                )
            )
        )
);

导致

{
  "query": {
    "bool": {
      "filter": [
        {
          "terms": {
            "name": [
              "name1",
              "name2"
            ]
          }
        },
        {
          "terms": {
            "color": [
              "orange",
              "red"
            ]
          }
        }
      ]
    }
  }
}

NEST also has the concept of conditionless queries,也就是说,如果确定某个查询是无条件的,那么它将序列化为请求的一部分。

无条件意味着什么?那么,这取决于查询;例如,在terms查询的情况下,如果满足以下任何条件,则视为无条件

  • field没有值
  • 术语值列表为null
  • 条款值为空集合
  • 术语值列表包含值,但它们都是null或空字符串

演示

var emptyNames = new string[] {};
string[] nullColors = null;

client.SearchAsync<MyDocument>(s =>
s.Index("myindex")
    .Query(q => q
        .Bool(bq => bq
            .Filter(
                fq => fq.Terms(t => t.Field(f => f.Name).Terms(emptyNames)),
                fq => fq.Terms(t => t.Field(f => f.Color).Terms(nullColors)))
        )
    )
);

结果

{}

无条件查询可以使编写NEST查询更容易,因为在构造查询之前不需要检查集合是否具有值。您可以基于每个查询更改无条件语义using .Strict() and .Verbatim()

答案 2 :(得分:0)

var searchResponse = client.Search<EventData>(s => s
            .From(0)
            .Query(q => q
                    .Bool(bq => bq
                    .Filter(
                            fq => fq.Terms(t => t.Field(f => f.Client.Id).Terms(17)),
                            fq => fq.Terms(t => t.Field(f => f.Item.Id).Terms(**new[] { 34983, 35430, 35339, 35300 }**)), 
                            fq => fq.Terms(t=>t.Field(f=>f.Event).Terms("Control de Panico")),
                            fq => fq.DateRange(dr => dr.Field(f => f.DateTime)
                                .GreaterThanOrEquals(new DateTime(2018, 07, 01))
                                .LessThanOrEquals(new DateTime(2018, 10, 02)))
                            )
                  ))
            .Size(2000)
            .Sort(g => sortDescriptor)
            );