How to create nested array in realm without key(React Native)

Question

{
    "a": [
        [
            {
              "_id": "57e55b64016c3551c025abc1",
              "title": "Main Campus"
            },
            {
              "_id": "5810e2e27064497f74ad4874",
              "title": "Ahm Campus"
            },
            {
              "_id": "5d5d2633a1d0680620ac3cce",
              "title": "Baroda"
            },
            {
              "_id": "5d5d3af3a1d0680620ac3ef8",
              "title": "India"
            }
          ],
          [
            {
              "_id": "57e55b64016c3551c025abc1",
              "title": "Main Campus"
            },
            {
              "_id": "5810e2e27064497f74ad4874",
              "title": "Ahm Campus"
            },
            {
              "_id": "5d5d2633a1d0680620ac3cce",
              "title": "Baroda"
            },
            {
              "_id": "5d5d3af3a1d0680620ac3ef8",
              "title": "India"
            }
          ]

    ]
  }

How to create the schema in the realm(React native) for this type of JSON object. I tried all possible ways but did not found any specific solution. Basically, it is a nested array where the second array does not have any specific key(I tried with key it works fine but I want to do it without adding key).

Answer 1

You can use something like:

const ParentSchema = {
  name: "parent",
  properties: {
    key: "string",
    values: "Value[]"
  }
};

const ValueSchema = {
  name: "Value",
  embedded: true,
  properties: {
    _id: "string",
    title: "string"
  }
};

You can insert objects like:

realm.write(() => {
  realm.create("Parent", { key: "a", values: [
      { _id: "57e55b64016c3551c025abc1", title: "Main Campus" },
      { _id: "5810e2e27064497f74ad4874", title: "Ahm Campus" }
    ]
  });
});

Documentation: https://docs.mongodb.com/realm/node/data-model

Answer 2

As of now there is no way to insert direct value in Realm database without key so for now we need to modify data and then we can store in following schema.

const ParentSchema = {
  name: "parent",
  properties: {
   a: "level[]"
  }
};

const level = {
    name: 'level',
    properties: {
        level: 'sites[]'
    }
}
const sites = {
    name: 'sites',
    properties: {
        sites: 'site[]'
    }
}
const site = {
    name: 'site',
    properties: {

        title: 'string?',
        _id: 'string?',
        version: 'int?',
    }
}

Data modification need to done like following.

var a = {
    level: []
 }

data.a.map((Site, index) => {
         const sites = []
         Site.map((s) => { sites.push(s)})
         a.level.push({sites})
 })