Question

我有这个结构

{
"_id" : "EbtLm2Nmb79WWryEr",
"notificationByUsers" : {
    "all" : [ 
        {
            "account_id" : "X5PjY66JAwgoxDb4L",
            "date" : ISODate("2016-07-27T13:48:17.154Z"),
            "value" : null
        }, 
        {
            "account_id" : "2C2FKXaKtmeRMNT3E",
            "date" : ISODate("2016-07-27T13:53:10.296Z"),
            "value" : "Instant"
        }, 
        {
            "account_id" : "6Np35oj63cavF4RHs",
            "date" : ISODate("2016-07-28T07:18:22.696Z"),
            "value" : "Instant"
        }
    ]
}

}

我正在查询

db.Collection.findOne({_id: EbtLm2Nmb79WWryEr, 'notificationByUsers.all':{$elemMatch:{account_id: "2C2FKXaKtmeRMNT3E"}}}, {_id:0, 'notificationByUsers.all.$': 1})

它在roboMongo中返回

{
 "notificationByUsers" : {
"all" : [ 
    {
        "account_id" : "2C2FKXaKtmeRMNT3E",
        "date" : ISODate("2016-07-27T13:53:10.296Z"),
        "value" : "Instant"
    }
]
}

但在Meteor中，它会使用此查询返回所有数组元素。我想要特定数组元素的结果在robomongo中工作。

Answer 1

您可以使用字段投影来完成此操作，例如：

MyCollection.findOne({},{ fields : {_id:0, 'notificationByUsers.all':1}});

这将返回如下对象：

{
 "notificationByUsers" : {
"all" : [ 
    {
        "account_id" : "2C2FKXaKtmeRMNT3E",
        "date" : ISODate("2016-07-27T13:53:10.296Z"),
        "value" : "Instant"
    }
]
}

获取特定的数组元素 - Meteor Mongodb

1 个答案: