Lets say my documents look like this :

  _id: "6285e9a7aff93ead37ec50ad",
  date: "2022-04-28T10:51:37.923Z",
  devices: {
    tablets: [
      {
        brand: "samsung",
        model: "s20"
      },
      {
        brand: "samsung",
        model: "s21"
      },
      {
        brand: "apple",
        model: "ipad_mini"
      },
    ],
    phones: [
      {
        brand: "samsung",
        model: "galaxy_s20"
      },
      {
        brand: "samsung",
        model: "galaxy_s20_lite"
      }
    ],
    laptops: []
  }
}

how would i query and return all documents that contain at least an "apple" value in "brand" property wherever inside the "devices" property ?

CodePudding user response：

When you have more dynamic keys, you can use

db.collection.aggregate([
  {
    $project: {
      "d": {
        "$objectToArray": "$devices"
      }
    }
  },
  {
    "$match": {
      "d.v.brand": "apple"
    }
  }
])

You need to restructure the data if required. It returns if there is atleast one match.

playground

db.collection.aggregate([
  {
    $project: {
      "d": {
        "$objectToArray": "$devices"
      }
    }
  },
  {
    "$match": {
      "d.v.brand": "apple"
    }
  },
  {
    "$project": {
      "devices": { //To reshape back
        "$arrayToObject": "$d"
      }
    }
  }
])

Playground