查询文档以获取数组值为空的记录

时间:2019-12-20 17:38:13

标签: mongodb

我有一个这样的文件:

{
    "_id" : "4mDYgt6gID",
    ...
    "MultipleChoiceQuestions" : [ 
        {
            ...
            "LeadInFile" : null,
            ...
        },
        {
            ...
            "LeadInFile" : 'some string',
            ...
        }
    ],
    ...
}

如何查询LeadInFile中具有非空值的任何文档?

我正在尝试不同的方法,目前类似这样 db.getCollection('QuizTime:Quizzes').find({"MultipleChoiceQuestions": [{ "LeadInFile": { $ne: null}}]});

正在返回0条记录。

1 个答案:

答案 0 :(得分:1)

查询的当前形式是:

  

查找server.host: "172.31.2.197" elasticsearch.hosts: http://172.31.2.197:9200 elasticsearch.ssl.verificationMode: none #elasticsearch.username: admin #elasticsearch.password: admin #elasticsearch.requestHeadersWhitelist: ["securitytenant","Authorization"] opendistro_security.enabled: false opendistro_security.multitenancy.enabled: false #opendistro_security.multitenancy.tenants.preferred: ["Private", "Global"] #opendistro_security.readonly_mode.roles: ["kibana_read_only" MultipleChoiceQuestions的文档

尝试使用dot notation;它用于访问嵌入式文档中的数组元素或字段。例如:

[{ "LeadInFile": { $ne: null}}]