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mongodb查询嵌入式文档

Jun 07, 2016 pm 05:45 PM
mongodb Embedded document Inquire

db.getCollection("mobiles").ensureIndex({ "params.name": 1, "params.value": 1 }); db.getCollection("mobiles").insert({ "_id": 1, "name": "ME525", "brand": "摩托罗拉", "params": [ {"name": "待机时间", "value": 200}, {"name": "外观设计", "va

db.getCollection("mobiles").ensureIndex({
    "params.name": 1,
    "params.value": 1
});

db.getCollection("mobiles").insert({
    "_id": 1,  
    "name": "ME525",
    "brand": "摩托罗拉",
    "params": [
        {"name": "待机时间", "value": 200},
        {"name": "外观设计", "value": "直板"}
    ]
});

db.getCollection("mobiles").insert({
    "_id": 2,
    "name": "E7",
    "brand": "诺基亚",
    "params": [  
        {"name": "待机时间", "value": 500},
        {"name": "外观设计", "value": "滑盖"}
    ]
});
  

 

如果想查询待机时间大于100小时,网站空间,并且外观设计是直板的手机,香港空间,需要按照如下方式查询:

db.getCollection("mobiles").find({
    "params": {
        $all: [
            {$elemMatch: {"name": "待机时间", "value": {$gt: 100}}},
            {$elemMatch: {"name": "外观设计", "value": "直板"}}
        ]
    }
});
  

 

注:查询中用到的$all,美国空间,$elemMatch等高级用法的详细介绍请参考官方文档中相关说明。

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