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如何使用Java从MongoDB中的所有文档中获取相同密钥的值?_Java_Mongodb - Fatal编程技术网

如何使用Java从MongoDB中的所有文档中获取相同密钥的值?

如何使用Java从MongoDB中的所有文档中获取相同密钥的值?,java,mongodb,Java,Mongodb,我是mongodb的新手。这是我的Mongodb文档,我只需要名称值 { "_id" : ObjectId("5da527f784a58d78fcd0b177"), "name" : "Jabed", "email" : "jabed@gmail.com", "Sex" : "male", &quo

我是mongodb的新手。这是我的Mongodb文档,我只需要名称值

{
    "_id" : ObjectId("5da527f784a58d78fcd0b177"),
    "name" : "Jabed",
    "email" : "jabed@gmail.com",
    "Sex" : "male",
    "age" : "19",
    "address" : "Kochukhet, Dhaka",
    "Contct" : "01797259329"
}

{
    "_id" : ObjectId("5da6f415f2bdee4b90cf41d0"),
    "name" : "Bulbul Gulzer Deb",
    "email" : "gulzer.deb@gmail.com",
    "Sex" : "male",
    "age" : "19",
    "address" : "Narinda, Dhaka",
    "Contct" : "01756223666"
}

{
    "_id" : ObjectId("5dd771907607c3e12d9183d7"),
    "name" : "Aniruddha Dey",
    "email" : "aniruddha.dey@gmail.com",
    "Sex" : "male",
    "age" : "14",
    "address" : "Narinda, Dhaka",
    "Contct" : "01745706020"
}
预期产出将为

Jabed
Bulbul Gulzer Deb
Aniruddha Dey
使用投影:

db.yourdocument.find( {}, { name: 1, _id: 0 } )

可以在db.collection.distinct(“nameoffield”)中找到对投影字段的更多控制,或者您可以看到这个链接,我如何使用java实现它?