c# – Elasticsearch NEST:不带通配符的部分/全文搜索

我想为我的用户提供搜索引擎.假设用户类是:

public class User
{
    public string Code { get; set; }
    public string Name { get; set; }
}

我的数据库中有这样的用户:

(1) new User { Code = "XW1234", Name = "John Doe" }, 
(2) new User { Code = "AD4567", Name = "Jane Doe" }

所以:
当我的查询是:“doe”(介意小写)我想看(1)和(2)
当我的查询是:“4”我想看(1)和(2)
当我的查询是:“x”我想看(1)
当我的查询是:“ja”我想看(2)
我希望像SQL中的%doe%一样工作.请不要介意查询长度 – 我最少使用3个字母.这只是一个例子.

我有一个带通配符的解决方案 – 工作但性能很差.

我试图配置索引使用ngram tokenizer但没有成功 – 我收到了一个空集合.

我也检查了这个(“以”开头“的方法):
https://www.elastic.co/guide/en/elasticsearch/guide/current/_index_time_search_as_you_type.html
没有成功.

请提供C#代码.我不知道我是否正确翻译了弹性搜索jsons.

编辑
根据第一条评论,我试过这个:

private const string DefaultIndexName = "test";
private const string ElasticSearchServerUri = @"http://192.168.99.100:32769";

private static readonly IndexName UsersIndexName = "users";

public IElasticClient CreateElasticClient()
{
    var settings = CreateConnectionSettings();

    var client = new ElasticClient(settings);

    var studentsIndexDescriptor = new CreateIndexDescriptor(UsersIndexName)
        .Mappings(ms => ms
            .Map<User>(m => m
                .Properties(ps => ps
                    .String(s => s
                        .Name(n => n.Code)
                        .Analyzer("substring_analyzer")))));
    client.CreateIndex(UsersIndexName, descriptor => studentsIndexDescriptor
        .Settings(s => s
            .Analysis(a => a
                .Analyzers(analyzer => analyzer
                    .Custom("substring_analyzer", analyzerDescriptor => analyzerDescriptor.Tokenizer("standard").Filters("lowercase", "substring")))
                .TokenFilters(tf => tf
                    .NGram("substring", filterDescriptor => filterDescriptor.MinGram(2).MaxGram(15))))));

    return client;
}

private static ConnectionSettings CreateConnectionSettings()
{
    var uri = new Uri(ElasticSearchServerUri);
    var settings = new ConnectionSettings(uri);
    settings
        .DefaultIndex(DefaultIndexName);

    return settings;
}

我使用了这个查询:

public IEnumerable<User> Search(string query)
{
    var result = elasticClient.Search<User>(descriptor => descriptor
        .Query(q => q
            .QueryString(queryDescriptor => queryDescriptor.Query(query).Fields(fs => fs.Fields(f1 => f1.Code)))));
    return result.Documents;
}

没工作.

我尝试了代码:“1234”和“5678”.我试图用“23”,“5”查询 – 没有结果.
当我搜索“1234”时 – 它返回正确的用户.

解决方法:

我怀疑你的代码:

>为用户建立索引时,不指定用户索引,因此将用户索引到默认索引中.
>搜索时,不指定用户索引,因此将查询默认索引test.此索引包含索引文档,但不使用substring_analyzer分析代码字段,因为此分析在users索引中定义.

NEST在ConnectionSettings,.InferMappingFor< T>()上提供配置选项,以将特定POCO类型与特定索引名称相关联;如果未在请求中指定并且优先于默认索引,则将使用此索引.

var uri = new Uri(ElasticSearchServerUri);
var settings = new ConnectionSettings(uri)
    .DefaultIndex(DefaultIndexName)
    .InferMappingFor<User>(d => d
        .IndexName(UsersIndexName)
    );

你的其余代码是正确的.这是一个完整的工作示例

private const string DefaultIndexName = "test";
private const string ElasticSearchServerUri = @"http://localhost:9200";
private const string UsersIndexName = "users";

void Main()
{
    var client = CreateElasticClient();

    var users = new[] {
        new User { Code = "XW1234", Name = "John Doe" },
        new User { Code = "AD4567", Name = "Jane Doe" }
    };

    client.IndexMany(users);

    // refresh the index after indexing so that the documents are immediately 
    // available for search. This is good for testing, 
    // but avoid doing it in production.
    client.Refresh(UsersIndexName);

    var result = client.Search<User>(descriptor => descriptor
        .Query(q => q
            .QueryString(queryDescriptor => queryDescriptor
                .Query("1234")
                .Fields(fs => fs
                    .Fields(f1 => f1.Code)
                )
            )
        )
    );

    // outputs 1
    Console.WriteLine(result.Total);
}

public class User
{
    public string Code { get; set; }
    public string Name { get; set; }
}

public IElasticClient CreateElasticClient()
{
    var settings = CreateConnectionSettings();
    var client = new ElasticClient(settings);

    // this is here so that the example can be re-run.
    // Remove this!
    if (client.IndexExists(UsersIndexName).Exists)
    {
        client.DeleteIndex(UsersIndexName);
    }

    client.CreateIndex(UsersIndexName, descriptor => descriptor
        .Mappings(ms => ms
            .Map<User>(m => m
                .AutoMap()
                .Properties(ps => ps
                    .String(s => s
                        .Name(n => n.Code)
                        .Analyzer("substring_analyzer")
                    )
                )
            )
        )
        .Settings(s => s
            .Analysis(a => a
                .Analyzers(analyzer => analyzer
                    .Custom("substring_analyzer", analyzerDescriptor => analyzerDescriptor
                        .Tokenizer("standard")
                        .Filters("lowercase", "substring")
                    )
                )
                .TokenFilters(tf => tf
                    .NGram("substring", filterDescriptor => filterDescriptor
                        .MinGram(2)
                        .MaxGram(15)
                    )
                )
            )
        )
    );

    return client;
}

private static ConnectionSettings CreateConnectionSettings()
{
    var uri = new Uri(ElasticSearchServerUri);
    var settings = new ConnectionSettings(uri)
        .DefaultIndex(DefaultIndexName)
        .InferMappingFor<User>(d => d
            .IndexName(UsersIndexName)
        );

    return settings;
}
上一篇:c# – 使用NEST和.NET从Elasticsearch返回多个派生类实例


下一篇:SQL 根据关联表更新主表中字段数据