How is data organized in IndexedDB?

Question

Ponu Maurya · Answer

In IndexedDB, data is organized in a structured, hierarchical format that allows efficient storage and retrieval of complex objects. Here's a breakdown of the structure:
Data Organization in IndexedDB
1. Database
The top-level container.Each origin (domain + protocol) can have multiple databases.Created/opened with indexedDB.open(name, version).
2. Object Stores (like tables)
Contain actual records (JavaScript objects).
Each object store has:
A key path (e.g., "id").Optionally, auto-increment keys.Example: users, orders, posts object stores.
db.createObjectStore('users', { keyPath: 'id', autoIncrement: true });
3. Records (stored objects)
Each entry in an object store.
Key-value pair: the key is unique in that store.
Example:
{
  id: 1,
  name: "Alice",
  email: "alice@example.com"
}
4. Indexes (for fast lookup)
Optional but powerful.Allow fast querying on fields other than the primary key.Can be unique (no duplicates) or not.
store.createIndex('emailIndex', 'email', { unique: true });
5. Transactions
All reads/writes must happen in a transaction.Can be read-only or read-write.Multiple object stores can be accessed in a single transaction.
Hierarchy Summary
IndexedDB
│
└── Database (e.g., 'AppDB')
    │
    ├── Object Store: 'users'
    │   ├── Record: { id: 1, name: 'Alice' }
    │   ├── Record: { id: 2, name: 'Bob' }
    │   └── Index: 'emailIndex' on 'email'
    │
    └── Object Store: 'orders'
        └── Record: { id: 101, userId: 1, item: 'Book' }
Example Flow
const request = indexedDB.open('AppDB', 1);
request.onupgradeneeded = (e) =andgt; {
    const db = e.target.result;
    const userStore = db.createObjectStore('users', { keyPath: 'id' });
    userStore.createIndex('email', 'email', { unique: true });
};
request.onsuccess = (e) =andgt; {
    const db = e.target.result;
    const tx = db.transaction('users', 'readwrite');
    const store = tx.objectStore('users');
    store.add({ id: 1, name: "Alice", email: "alice@example.com" });
};
Key Takeaways
Database → contains Object StoresObject Stores → contain RecordsIndexes → speed up lookups on fieldsAll operations happen inside Transactions

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How is data organized in IndexedDB?

Ponu Maurya

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1 Answers

Data Organization in IndexedDB

1. Database

2. Object Stores (like tables)

3. Records (stored objects)

4. Indexes (for fast lookup)

5. Transactions

Hierarchy Summary

Example Flow

Key Takeaways

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