Question

我有一个时间序列文档来存储设备的多个传感器数据/ 1 /。在示例中，deviceId A-1具有

1)geo info("longitude" : 0.6644560403052914, "latitude" : 0.7165033050936503 ),
2)temperature, ("sensorType" : "temperature","sensorValue" : "14")
3)humidity, ("sensorType" : "humidity", "sensorValue" : "12")

查询基于createDate的时间范围，如何使用一个查询或一个聚合来获取三个地理信息，温度和湿度数组以及如何选择索引和索引类型？

/ 1 /数据结构

{
        "_id" : "7736b113586a4314bfbe036cf6b3e34c",
        "createDate" : ISODate("2016-08-30T16:30:33.007Z"),
        "deviceId" : "A-1",
        "vendorCode" : "01",
        "longitude" : 0.6644560403052914,
        "latitude" : 0.7165033050936503,
         "sensorList" : [
                {
                        "_id" : "1802b2792cac4529b269d5e2c9398e80",
                        "createDate" : ISODate("2016-08-30T16:30:33.007Z"),
                       "sensorType" : "temperature",
                        "sensorId" : 1,
                        "sensorValue" : "14"
                },
                {
                        "_id" : "ddbe2d76770c42cfabc8d22d7c732826",
                        "createDate" : ISODate("2016-08-30T16:30:33.007Z"),
                        "sensorType" : "humidity",
                        "sensorId" : 2,
                        "sensorValue" : "12"
                }
        ]
}

Answer 1

这还不是答案，但我想告诉你我在哪里。我有点难以在一个聚合中完成这一切。

> db.foo.aggregate([
...     // First project out the fields we don't need.  geoInfo only requires latitude and longitude so let's take care of it first.
...     {"$project": {"_id": 0, "geoInfo": {"longitude": "$longitude", "latitude": "$latitude"}, "sensorList": 1}},
...     // Now let's group based on the sensorType, we need to unwind our array first
...     {"$unwind": "$sensorList"},
...     {"$group": {
...         "_id": "$sensorList.sensorType",
...         "value": {"$first": "$sensorList.sensorValue"},
...         "geoInfo": {"$push": "$geoInfo"}
...     }}
... ]);

{ "_id" : "humidity", "value" : "12", "geoInfo" : [ { "longitude" : 0.6644560403052914, "latitude" : 0.7165033050936503 } ] }

{ "_id" : "temperature", "value" : "14", "geoInfo" : [ { "longitude" : 0.6644560403052914, "latitude" : 0.7165033050936503 } ] }

MongoDB：查询或聚合以一次性将不同的度量数据转换为数组

1 个答案: