从mongodb阵列获取最近2天/分钟

Question

I have mongodb data like this:

"_id" : "sensor-2",
"data" : [ 
    {
        "sensor" : {
            "intensitas" : 3,
            "arus" : 0.1
        },
        "tanggal" : ISODate("2018-08-05T21:00:19.552+07:00")
    }, 
    {
        "sensor" : {
            "intensitas" : 8,
            "arus" : 0.1
        },
        "tanggal" : ISODate("2018-08-05T21:04:40.594+07:00")
    }, 
    {
        "sensor" : {
            "intensitas" : 6,
            "arus" : 0.1
        },
        "tanggal" : ISODate("2018-08-05T21:05:43.647+07:00")
    }, 
    {
        "sensor" : {
            "intensitas" : 13,
            "arus" : 0.1
        },
        "tanggal" : ISODate("2018-08-04T21:05:45.150+07:00")
    }, 
    {
        "sensor" : {
            "intensitas" : 15,
            "arus" : 0.05
        },
        "tanggal" : ISODate("2018-08-04T21:05:46.651+07:00")
    }, 
    {
        "sensor" : {
            "intensitas" : 13,
            "arus" : 0.05
        },
        "tanggal" : ISODate("2018-08-04T21:05:51.152+07:00")
    }, 
    {
        "sensor" : {
            "intensitas" : 8,
            "arus" : 0.05
        },
        "tanggal" : ISODate("2018-08-04T21:05:52.654+07:00")
    }, 
    {
        "sensor" : {
            "intensitas" : 11,
            "arus" : 0.05
        },
        "tanggal" : ISODate("2018-08-04T21:05:58.756+07:00")
    }, 
    {
        "sensor" : {
            "intensitas" : 3,
            "arus" : 0.05
        },
        "tanggal" : ISODate("2018-08-07T21:05:58.757+07:00")
    }
]

I want to get the last 2 days or minutes from the array base from id, which "tanggal" is Date in English.

I've tried from this how to filter last 10 days records from mongoDb? but not what I want because after I get the data I want to average that last 2 days/minutes data.

Answer 1

To get the last 2 days you can do something like this:

db.getCollection('items').aggregate([
  {
      $unwind: '$data'
  },
  {
    $match: {
      'data.tanggal': {
        $gt: (new Date(new ISODate()-2*1000*60*60*24))
      }
    }
  },
  {
    $sort: {
      'data.tanggal': -1
    }
  }
])

last 2 minutes you just remove the 24 from the date calc so you get:

$gt: (new Date(new ISODate()-2*1000*60*60))