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查询筛选条件、和检索对象数组

您可以使用 returnScope 选项设立查询上下文，并将对象数组作为单个文档返回。

要求

要使用 returnScope 将嵌套对象作为独立文档检索，您必须：

将对象数组索引为 embeddedDocuments 类型。
为要检索的嵌套字段定义 storedSource。MongoDB 搜索仅返回在 storedSource 中定义的字段。
在查询中将 returnStoredSource 选项设置为 true。

语法

returnScope 查询中包含以下语法：

{
  $search: {
   "<operator>": {
      <operator-specification>,
   },
   "returnScope": {
      "path": "<embedded-documents-field-to-retrieve>"
   },
   "returnStoredSource": true
  }
}

{
  $searchMeta: {
   "returnScope": {
      "path": "<embedded-documents-field-to-retrieve>"
   },
   "returnStoredSource": true
  },
  "facet": {
    "<operator>": {
      <operator-specification>,
   },
    "facets": {
      <facet-definition>
    }
  }
}

要了解有关查询语法的更多信息，请参阅$search 。

行为

returnScope 选项设置查询的检索上下文。如果您在查询中指定 returnScope，MongoDB Search 就会像处理单个文档一样对每个嵌入式文档进行评分、排序和计数。

Considerations

在您的操作符规范中，您必须指定要查询的字段的完整路径。

当您使用 returnScope 选项时，MongoDB Search 仅返回您在 embeddedDocument 中配置为 storedSource 的字段。embeddedDocument 路径之外的字段（例如根级字段）和未配置为 storedSource 的字段不会被返回。

示例

以下示例演示了如何在查询中使用 returnScope 选项。这些示例使用 sample_training.companies 示例数据集。如果您在集群上加载数据并在集合的字段上创建示例索引，则可以针对示例数据运行以下查询。

样本索引

1 {
2   "mappings": { 
3     "dynamic": false,
4     "fields": { 
5       "funding_rounds": { 
6         "type": "embeddedDocuments",
7         "dynamic": true,
8         "fields": {
9           "investments": {
10             "type": "embeddedDocuments",
11             "dynamic": true
12           }
13         },
14         "storedSource": {
15           "include": [
16             "round_code", 
17             "raised_currency_code",
18             "raised_amount",
19             "investments.person",
20             "investments.financial_org"
21           ] 
22         },
23       } 
24     }
25   }
26 }

前面的索引定义将MongoDB 搜索配置为：

将 funding_rounds 和 funding_rounds.investments 字段作为 embeddedDocuments 类型进行索引。
为嵌套在 funding_rounds 和 funding_rounds.investments 对象数组中的所有可动态索引的字段建立索引。
将以下字段存储在 mongot 上：
- funding_rounds.round_code
- funding_rounds.raised_currency_code
- funding_rounds.raised_amount
- funding_rounds.investments.person
- funding_rounds.investments.financial_org

您可以使用embeddedDocument 操作符对 funding_rounds 和 funding_rounds.investments 字段进行逐元素查询。以下章节展示了一些使用 returnScope 选项将 embeddedDocuments 字段作为单独文档检索的示例查询。

来自 sample_training.companies 集合的示例文档结构

{
  ...,
  "funding_rounds": [
    {
      "id": <integer>,
      "round_code": "<string>",
      "source_url": "<string>",
      "source_description": "<string>",
      "raised_amount": <integer>,
      "raised_currency_code": "<string>",
      "funded_year": <integer>,
      "funded_month": "<string>",
      "funded_day": "<string>",
      "investments": [
         {
           "company": "<string>",
           "financial_org": {
             "name": "<string>",
             "permalink": "<string>"
           },
           "person": {
             "first_name": "<string>",
             "last_name": "<string>",
             "permalink": "<string>"
           }
         },
         ...
      ]
    },
    ...
  ],
  ...
}

样本查询

以下各节演示了使用 returnScope 选项检索存储在 mongot 上的 embeddedDocuments 类型字段的示例查询。

简单查询

查询和检索嵌入式文档字段。

以下查询使用 range（MongoDB搜索操作符）在 funding_rounds.raised_amount 字段中查询大于和等于 5000000 且小于和等于 10000000 的金额。它使用 returnScope 选项查询范围设置为 funding_rounds字段。它返回 funding_rounds 对象数组中存储的所有字段，包括使用 returnStoredSource 选项存储的 funding_rounds.investments 对象数组中的字段。它将结果数量限制为仅包含 5 个 funding_rounds 文档。

1 db.companies.aggregate(
2   {
3     "$search": {
4       "range": {
5         "path": "funding_rounds.raised_amount",
6         "gte": 5000000,
7         "lte": 10000000
8       },
9       "returnStoredSource": true,
10       "returnScope": {
11         "path": "funding_rounds"
12       }
13     }
14   },
15   {
16     "$limit": 5
17   }
18 )

[
  {
    round_code: 'a',
    raised_amount: 5250000,
    raised_currency_code: 'USD',
    investments: [
      {
        financial_org: {
          name: 'Frazier Technology Ventures',
          permalink: 'frazier-technology-ventures'
        },
        person: null
      },
      {
        financial_org: { name: 'Trinity Ventures', permalink: 'trinity-ventures' },
        person: null
      }
    ]
  },
  {
    round_code: 'b',
    raised_amount: 9500000,
    raised_currency_code: 'USD',
    investments: [
      {
        financial_org: { name: 'Accel Partners', permalink: 'accel-partners' },
        person: null
      },
      {
        financial_org: {
          name: 'Frazier Technology Ventures',
          permalink: 'frazier-technology-ventures'
        },
        person: null
      },
      {
        financial_org: { name: 'Trinity Ventures', permalink: 'trinity-ventures' },
        person: null
      }
    ]
  },
  {
    round_code: 'a',
    raised_amount: 5000000,
    raised_currency_code: 'USD',
    investments: [
      {
        financial_org: {
          name: 'Charles River Ventures',
          permalink: 'charles-river-ventures'
        },
        person: null
      },
      {
        financial_org: {
          name: 'Union Square Ventures',
          permalink: 'union-square-ventures'
        },
        person: null
      },
      {
        financial_org: null,
        person: {
          first_name: 'Marc',
          last_name: 'Andreessen',
          permalink: 'marc-andreessen'
        }
      },
      {
        financial_org: null,
        person: {
          first_name: 'Dick',
          last_name: 'Costolo',
          permalink: 'dick-costolo'
        }
      },
      {
        financial_org: null,
        person: {
          first_name: 'Naval',
          last_name: 'Ravikant',
          permalink: 'naval-ravikant'
        }
      },
      {
        financial_org: null,
        person: {
          first_name: 'Ron',
          last_name: 'Conway',
          permalink: 'ron-conway'
        }
      },
      {
        financial_org: null,
        person: {
          first_name: 'Chris',
          last_name: 'Sacca',
          permalink: 'chris-sacca'
        }
      },
      {
        financial_org: null,
        person: {
          first_name: 'Greg',
          last_name: 'Yaitanes',
          permalink: 'greg-yaitanes'
        }
      },
      {
        financial_org: null,
        person: {
          first_name: 'Brian',
          last_name: 'Pokorny',
          permalink: 'brian-pokorny'
        }
      },
      {
        financial_org: { name: 'SV Angel', permalink: 'sv-angel' },
        person: null
      }
    ]
  },
  {
    round_code: 'e',
    raised_amount: 5166511,
    raised_currency_code: 'USD',
    investments: []
  },
  {
    round_code: 'b',
    raised_amount: 9000000,
    raised_currency_code: 'USD',
    investments: [
      {
        financial_org: {
          name: 'Charles River Ventures',
          permalink: 'charles-river-ventures'
        },
        person: null
      },
      {
        financial_org: { name: 'Redpoint Ventures', permalink: 'redpoint-ventures' },
        person: null
      },
      {
        financial_org: {
          name: 'The Kinsey Hills Group',
          permalink: 'kinsey-hills-group'
        },
        person: null
      }
    ]
  }
]

复合查询

查询并检索多个嵌入式文档字段。

以下查询使用 compound 操作符在同一查询中搜索多层嵌套 embeddedDocuments 字段：

必须与 ``funding_rounds.raised_currency_code`` 匹配与 USD
应将 funding_rounds.investments.financial_org.name 与 Trinity Ventures 匹配

它会返回 funding_rounds 对象数组内存储的所有字段，包括 funding_rounds.investments 中的字段。它将结果数量限制为 5 funding_rounds 文档。

1 db.companies.aggregate(
2   {
3     "$search": {
4       "compound": {
5         "must": [{
6           "text": {
7             "path": "funding_rounds.raised_currency_code",
8             "query": "usd"
9           }
10         }],
11         "should": [{
12           "phrase": {
13             "path": "funding_rounds.investments.financial_org",
14             "query": "Trinity Ventures",
15           }
16         }]
17       },
18       "returnStoredSource": true,
19       "returnScope": {
20         "path": "funding_rounds"
21       }
22     }
23   },
24   {
25     "$limit": 5
26   }
27 )

[
  {
    round_code: 'a',
    raised_amount: 5250000,
    raised_currency_code: 'USD',
    investments: [
      {
        financial_org: {
          name: 'Frazier Technology Ventures',
          permalink: 'frazier-technology-ventures'
        },
        person: null
      },
      {
        financial_org: { name: 'Trinity Ventures', permalink: 'trinity-ventures' },
        person: null
      }
    ]
  },
  {
    round_code: 'b',
    raised_amount: 9500000,
    raised_currency_code: 'USD',
    investments: [
      {
        financial_org: { name: 'Accel Partners', permalink: 'accel-partners' },
        person: null
      },
      {
        financial_org: {
          name: 'Frazier Technology Ventures',
          permalink: 'frazier-technology-ventures'
        },
        person: null
      },
      {
        financial_org: { name: 'Trinity Ventures', permalink: 'trinity-ventures' },
        person: null
      }
    ]
  },
  {
    round_code: 'c',
    raised_amount: 25000000,
    raised_currency_code: 'USD',
    investments: [
      {
        financial_org: { name: 'DAG Ventures', permalink: 'dag-ventures' },
        person: null
      },
      {
        financial_org: { name: 'Accel Partners', permalink: 'accel-partners' },
        person: null
      },
      {
        financial_org: { name: 'Trinity Ventures', permalink: 'trinity-ventures' },
        person: null
      },
      {
        financial_org: {
          name: 'Frazier Technology Ventures',
          permalink: 'frazier-technology-ventures'
        },
        person: null
      }
    ]
  },
  {
    round_code: 'angel',
    raised_amount: 500000,
    raised_currency_code: 'USD',
    investments: [
      {
        financial_org: null,
        person: {
          first_name: 'Peter',
          last_name: 'Thiel',
          permalink: 'peter-thiel'
        }
      },
      {
        financial_org: null,
        person: {
          first_name: 'Reid',
          last_name: 'Hoffman',
          permalink: 'reid-hoffman'
        }
      }
    ]
  },
  {
    round_code: 'a',
    raised_amount: 12700000,
    raised_currency_code: 'USD',
    investments: [
      {
        financial_org: { name: 'Accel Partners', permalink: 'accel-partners' },
        person: null
      },
      {
        financial_org: null,
        person: {
          first_name: 'Mark',
          last_name: 'Pincus',
          permalink: 'mark-pincus'
        }
      },
      {
        financial_org: null,
        person: {
          first_name: 'Reid',
          last_name: 'Hoffman',
          permalink: 'reid-hoffman'
        }
      }
    ]
  }
]

后退

searchSequenceToken

来年

跟踪

1	{
2	"mappings": {
3	"dynamic": false,
4	"fields": {
5	"funding_rounds": {
6	"type": "embeddedDocuments",
7	"dynamic": true,
8	"fields": {
9	"investments": {
10	"type": "embeddedDocuments",
11	"dynamic": true
12	}
13	},
14	"storedSource": {
15	"include": [
16	"round_code",
17	"raised_currency_code",
18	"raised_amount",
19	"investments.person",
20	"investments.financial_org"
21	]
22	},
23	}
24	}
25	}
26	}

1	db.companies.aggregate(
2	{
3	"$search": {
4	"range": {
5	"path": "funding_rounds.raised_amount",
6	"gte": 5000000,
7	"lte": 10000000
8	},
9	"returnStoredSource": true,
10	"returnScope": {
11	"path": "funding_rounds"
12	}
13	}
14	},
15	{
16	"$limit": 5
17	}
18	)

1	db.companies.aggregate(
2	{
3	"$search": {
4	"compound": {
5	"must": [{
6	"text": {
7	"path": "funding_rounds.raised_currency_code",
8	"query": "usd"
9	}
10	}],
11	"should": [{
12	"phrase": {
13	"path": "funding_rounds.investments.financial_org",
14	"query": "Trinity Ventures",
15	}
16	}]
17	},
18	"returnStoredSource": true,
19	"returnScope": {
20	"path": "funding_rounds"
21	}
22	}
23	},
24	{
25	"$limit": 5
26	}
27	)