如何从集合中获取动态子文档[No Array]

Question

有一个像这样的集合

MongoDB Enterprise datap:SECONDARY> db.employee.find({"id":"12345"},{rltns:1});
{
    "_id" : ObjectId("XXXXX"),
    "rltns" : {
        "MO" : {
            "field1" : "hi",
            "field2" : "hello",
            "field3" : "aloha",
            "field4" : "namaste",
            "field5" : "oi",
            },
        "FA" : {
            "field1" : "check01",
            "field2" : "check02",
            }
        }
    }
}

不同关系的数量可以是0,1或多个

我们只需要打印id和field1 / field2

的数据

如何获得以下格式的文件？

12345 | MO | hi | hello
12345 | FA | check01 | check02

Answer 1

您可以根据需要准备查询：

let projection : {};
for(let i = 0; i < numberOfValue; i++) {
    Object.assing(projection, {
        ["fields"+i]: 1
    });
}
db.employee.find({_id: "12345"}, projection, function(err, result) {

});