What are some best practices for working with IndexedDB in production?

Question

ICSM Computer · Answer

1. Use a Promise-Based Wrapper
The native IndexedDB API is verbose and callback-heavy. Use a wrapper to simplify it:
Recommended Libraries:
idb – Lightweight, Promise-basedDexie.js – Feature-rich, transaction-safe
import { openDB } from 'idb';
const db = await openDB('MyDB', 1, {
  upgrade(db) {
    db.createObjectStore('users', { keyPath: 'id' });
  },
});
2. 
Version Your Database Carefully
Use the onupgradeneeded event to manage schema changes:
const request = indexedDB.open("MyDB", 2);
request.onupgradeneeded = function (e) {
  const db = e.target.result;
  if (!db.objectStoreNames.contains("users")) {
    db.createObjectStore("users", { keyPath: "id" });
  }
};
Always use version guards like if (oldVersion andlt; 2) to support 
gradual upgrades.
3. Handle Errors Gracefully
Always attach onerror, onabort, and onblocked handlers:
request.onerror = (e) =andgt; console.error("DB error:", e.target.error);
request.onblocked = () =andgt; alert("Please close other tabs to upgrade database.");
Also wrap get/put operations in try/catch if using Promises.
4. 
Use Indexes for Fast Queries
Define indexes in onupgradeneeded for searchable fields:
const store = db.createObjectStore('users', { keyPath: 'id' });
store.createIndex('email', 'email', { unique: true });
Query using:
const index = store.index('email');
const request = index.get('user@example.com');
5. Avoid Large Synchronous Loops
IndexedDB is async. Don’t use tight for loops with put().Use async batching or await Promise.all([...]).
6. Clean Up Old Data
Use store.delete(key) or store.clear() to keep storage clean.If you cache server data, consider expiring old entries manually.
7. Request Persistent Storage (optional)
Prevent browsers from auto-clearing your data:
if (navigator.storage andand navigator.storage.persist) {
  const granted = await navigator.storage.persist();
  console.log("Persistence:", granted);
}
8. Watch Out for Incognito/Private Mode
IndexedDB might be unavailable or volatile in private mode (especially in Safari). Use feature detection:
if (!window.indexedDB) {
  alert("IndexedDB not supported.");
}
9. Structure Object Stores Smartly
Don’t overload one store. Use multiple stores if needed:
usersmessagessettings
Avoid deeply nested objects unless really needed.
10. Sync With Server Wisely
Use IndexedDB for caching and offline-first appsSync on reconnect or refreshUse flags like isSynced, updatedAt in records
Bonus: Performance Tips
Tip
Benefit
Use openCursor() for large reads
Low memory usage
Use indexes instead of scanning all
Faster lookup
Avoid redundant writes (check first)
Reduce I/O
Keep transactions short
Prevent locks and crashes
Summary Checklist
Use a wrapper (like idb)Version and upgrade schema correctlyHandle all errors and blocked eventsUse indexes for performanceKeep store structure clean and modularEnable persistent storage (optional)Gracefully handle private modePlan data sync and cleanup

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What are some best practices for working with IndexedDB in production?

ICSM Computer

Can you answer this question?

1 Answers

1. Use a Promise-Based Wrapper

Recommended Libraries:

2. Version Your Database Carefully

3. Handle Errors Gracefully

4. Use Indexes for Fast Queries

5. Avoid Large Synchronous Loops

6. Clean Up Old Data

7. Request Persistent Storage (optional)

8. Watch Out for Incognito/Private Mode

9. Structure Object Stores Smartly

10. Sync With Server Wisely

Bonus: Performance Tips

Summary Checklist

Liked By

Tip	Benefit
Use `openCursor()` for large reads	Low memory usage
Use indexes instead of scanning all	Faster lookup
Avoid redundant writes (check first)	Reduce I/O
Keep transactions short	Prevent locks and crashes