Elasticsearch：“条款”，“匹配词组”和“查询字符串”之间的区别 [英] Elasticsearch: Difference between "Term", "Match Phrase", and "Query String"

问题描述

Elasticsearch的新功能，试图更好地了解这些查询之间的区别。据我所知， term 匹配单个术语（匹配是否需要小写？）和两个 match短语和查询字符串匹配文本字符串。

New here to Elasticsearch and trying to get a better understanding on the difference between these queries. As far as I can tell, term matches a single term (needs to be lowercase for the match to work?), and both match phrase and query string matches a string of text.

推荐答案

term 查询按原样匹配单个术语：未分析。
因此，不必根据所索引的内容将其小写。

term query matches a single term as it is : the value is not analyzed. So, it doesn't have to be lowercased depending on what you have indexed.

如果提供了 Bennett 在索引时间并且不分析该值，以下查询将不返回任何内容：

If you provided Bennett at index time and the value is not analyzed, the following query won't return anything :

{
  "query": {
    "term" : { "user" : "bennett" }
  }
}

match_phrase 查询将分析输入，如果为查询字段定义了分析器，并找到符合以下条件的文档：

match_phrase query will analyze the input if analyzers are defined for the queried field and find documents matching the following criterias :

• 所有条款必须出现在字段中


• 它们必须具有与输入值相同的订单

• all the terms must appear in the field
• they must have the same order as the input value

例如，如果您索引以下文档（使用<$ c $字段 foo 的c> standard 分析器：

For example, if you index the following documents (using standard analyzer for the field foo):

{ "foo":"I just said hello world" }

{ "foo":"Hello world" }

{ "foo":"World Hello" }

T他的 match_phrase 查询将只返回第一个和第二个文档：

This match_phrase query will only return the first and second documents :

{
  "query": {
    "match_phrase": {
      "foo": "Hello World"
    }
  }
}

query_string 默认情况下，在 _ all 字段，其中包含同时包含多个文本字段的文本。最重要的是，它已解析并支持某些运算符（AND / OR ...），通配符等（请参见相关语法）。

query_string query search, by default, on a _all field which contains the text of several text fields at once. On top of that, it's parsed and supports some operators (AND/OR...), wildcards and so on (see related syntax).

作为 match_phrase 查询，将根据查询字段上设置的分析器对输入进行分析。

As the match_phrase queries, the input is analyzed according to the analyzer set on the queried field.

与 match_phrase 不同，分析后获得的术语不必顺序相同，除非用户在输入中使用了引号。

Unlike the match_phrase, the terms obtained after analysis don't have to be in the same order, unless the user has used quotes around the input.

例如，使用与以前相同的文档，此查询将返回所有文档：

For example, using the same documents as before, this query will return all the documents :

{
  "query": {
    "query_string": {
      "query": "hello World"
    }
  }
}

但是此查询将返回与2个相同的文档 match_phrase 查询：

But this query will return the same 2 documents as the match_phrase query :

{
  "query": {
    "query_string": {
      "query": "\"Hello World\""
    }
  }
}

关于这些查询的不同选项还有很多要说的，请查看相关文档：

There is much more to say about the different options for those queries, please take a look at the related documentation :

• 条款


• 匹配短语


• query_string

• term
• match_phrase
• query_string

希望这很清楚，它将有所帮助。

Hope this is clear enough and it will help.

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