const request = indexedDB.open('MyAppDB', 1);

request.onupgradeneeded = (event) => {
  const db = event.target.result;

  // Create object stores (like tables)
  const store = db.createObjectStore('users', {
    keyPath: 'id',
    autoIncrement: true
  });

  // Create indexes for querying
  store.createIndex('email', 'email', { unique: true });
  store.createIndex('name', 'name', { unique: false });
};

request.onsuccess = (event) => {
  const db = event.target.result;
  console.log('Database opened:', db);
};

request.onerror = (event) => {
  console.error('Database error:', event.target.error);
};

flowchart TD
    A["IndexedDB Database"]
    A --> B["Object Store: Users"]
    A --> C["Object Store: Posts"]

    B --> B1["Index: byEmail"]
    B --> B2["Index: byName"]

    C --> C1["Index: byUserId"]
    C --> C2["Index: byDate"]

// Version 2 adds a new object store
const request = indexedDB.open('MyAppDB', 2);

request.onupgradeneeded = (event) => {
  const db = event.target.result;

  // Check if store already exists
  if (!db.objectStoreNames.contains('posts')) {
    const store = db.createObjectStore('posts', { keyPath: 'id' });
    store.createIndex('userId', 'userId', { unique: false });
  }
};