Why Realm database in React Native? - Purpose & Use Cases

The Big Idea

What if your app's data could organize itself and never slow you down?

The Scenario

Imagine building a mobile app that stores user notes, contacts, or settings. You try to save this data using plain files or simple arrays. As your app grows, managing and retrieving this data becomes messy and slow.

The Problem

Using manual storage methods means you write lots of code to save, update, and fetch data. It's easy to make mistakes, lose data, or cause your app to freeze while loading. Handling complex data relationships is even harder and error-prone.

The Solution

Realm database is like a smart organizer for your app's data. It stores information efficiently, lets you query it easily, and keeps your app fast and smooth. It handles complex data and syncing without extra hassle.

Before vs After

✗ Before

const notes = [];
// Manually save and load notes from AsyncStorage
await AsyncStorage.setItem('notes', JSON.stringify(notes));
const savedNotes = JSON.parse(await AsyncStorage.getItem('notes'));

✓ After

import Realm from 'realm';

const NoteSchema = {
  name: 'Note',
  properties: {
    id: 'int',
    text: 'string'
  },
  primaryKey: 'id'
};

async function runRealm() {
  const realm = await Realm.open({schema: [NoteSchema]});
  realm.write(() => {
    realm.create('Note', {id: 1, text: 'Hello'});
  });
  const notes = realm.objects('Note');
  return notes;
}

What It Enables

With Realm, you can build apps that handle complex data easily, keep data synced, and run smoothly even with lots of information.

Real Life Example

Think of a chat app that saves messages, contacts, and settings locally. Realm helps keep all this data organized and instantly available, even offline.

Key Takeaways

Manual data storage is slow and error-prone for complex apps.

Realm database simplifies storing, querying, and syncing data.

It helps build fast, reliable apps that handle lots of data smoothly.