How to define realm schema for property of object (or dictionary) with array as its value?

Question

I have data that looks like this

PersonJSONData = {
    "key1": {
        "name": "odo",
        "age": 10,
        "favorites": {
            "food": ["rice", "chocolate", "sugar"],
            "game": [],
            "color": ["red"]
        },
    "key2": {
        "name": "yana",
        "age": 50,
        "favorites": {
            "band": [],
            "food": ["eggs"],
            "book": ["ABC", "how to cook"]
        }
    },
    ...
}}

How do I write the schema in realm for react native?

const personSchema = {
    name: "Person",
    properties: {
        name: string,
        age: int,
        // favorites: I don't know what to write here??
    }
}

I tried using the type dictionary ("{}") but it's giving me an error:

[Error: A mixed property cannot contain an array of values.]

and when I used the type "mixed" I get this error:

[Error: Only realm instances are supported.]

Do I need to create an object type for that? If so, how to do it when I don't know for sure what the keys in favorites are?

Here is my code to create and write the instance.

const PersonInstance = new Realm(schema: [personSchema] })

function writePerson(){
    const personKeys = Object.keys(PersonJSONData)

    try { 
        personKeys.forEach((key) => {
        const { name, age, favorites } = PersonJSONData[key]
        
        PersonInstance.write(() => {
          PersonInstance.create('Person', {
            name, age, favorites
          })}
            
        })
    } catch(err) {
        // error handling
    }
}

or should I change how I write into the database instead? Can anyone help me with this? Thanks in advance.

Everything in Realm is an Object so yes, you will create an object that represents that data in code. Now the really important bit - you're asking how to create the object schema and fortunately that's covered in depth in the Getting Started Guide [Defining an Object Schema](https://docs.mongodb.com/realm/sdk/react-native/#define-an-object-schema) — Jay, Jan 28 '22 at 21:37

score 0 · Answer 1 · answered Oct 24 '22 at 17:53

  const PERSON_SCHEMA = {
  name: 'person_schema',
  properties: {
    id: 'int?',
    data: {type: 'list', objectType: 'person_schema_data'},
  },
  primaryKey: 'id',
};

const PERSON_SCHEMA_DATA = {
  name: 'person_schema_data',
  properties: {
    name: 'string?',
    age: 'int?',
    favorites: {type: 'object', objectType: 'person_favorites'},
  },
};

const PERSON_SCHEMA_FAVORITES = {
  name: 'person_favorites',
  properties: {
    food: {type: 'list', objectType: 'string'},
    game: {type: 'list', objectType: 'string'},
    color: {type: 'list', objectType: 'string'},
  },
};

const realm = await Realm.open({
path:`person_schema_path`,
schema:[PERSON_SCHEMA,PERSON_SCHEMA_DATA,PERSON_SCHEMA_FAVORITES]
})

How to define realm schema for property of object (or dictionary) with array as its value?

1 Answers1