mongodb查询嵌入式文档
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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