I have a collection with documents in cosmosDB .How can I group each field distinct values using mongoDB?

Here is my sample data:

{
        "_id" : ObjectId("61ba65af74cf385ee93ad2c8"),
        "Car_brand":"A",
        "Plate_number":"5",
        "Model_year":"2015",
        "Company":"Tesla Motors"
    },
    {
        "_id" : ObjectId("61ba65af74cf385ee93ad2c9"),
        "Car_brand":"B",
        "Plate_number":"2",
        "Model_year":"2021",
        "Company":"Tesla Motors",
        
    },
    {
        "_id" : ObjectId("61ba65af74cf385ee93ad2ca"),
        "Car_brand":"B",
        "Plate_number":"2",
        "Model_year":"2011",
        "Company":"Lamborghini",
    }

expected:

   {
        
        "Car_brand":["A","B"]
        "Plate_number":["5","2"]
        "Model_year":["2015","2021","2011"]
        "Company":["Lamborghini","Tesla Motors"]
    }

CodePudding user response：

Option1: Here is how to do in mongoDB , I guess it is similar in cosmosDB:

db.collection.aggregate([
{
$group: {
  _id: null,
  Car_brand: {
    $push: "$Car_brand"
  },
  Plate_number: {
    $push: "$Plate_number"
  },
  Model_year: {
    $push: "$Model_year"
  },
  Company: {
    $push: "$Company"
  }
 }
}
])

playground

Option2: Later I have identified you need the distinct values , here is an example:

db.collection.aggregate([
{
  $group: {
  _id: null,
  Car_brand: {
    $addToSet: "$Car_brand"
  },
  Plate_number: {
    $addToSet: "$Plate_number"
  },
  Model_year: {
    $addToSet: "$Model_year"
  },
  Company: {
    $addToSet: "$Company"
  }
 }
}
])

playground2