How do you clean up stale or expired data periodically in IndexedDB (e.g., TTL)?

Question

ICSM · Answer

To clean up stale or expired data (TTL: Time-To-Live) periodically in
IndexedDB, you need to manually implement a cleanup strategy since IndexedDB has
no built-in TTL or expiration mechanism.
Here’s a complete approach:
Strategy to Clean Stale/Expired Data in IndexedDB
1. Store Timestamps with Your Data
Include an updatedAt or expiresAt field (timestamp) in each record:
{
  id: 'abc123',
  name: 'Item',
  data: '...',
  updatedAt: Date.now(),         // OR
  expiresAt: Date.now() + 3600 * 1000 // 1 hour TTL
}
2. Periodic Cleanup Function
You can create a scheduled cleanup function that deletes expired records.
async function cleanupExpiredData(db, tableName, ttlMs) {
  const now = Date.now();
  const table = db.table(tableName);
  await table.where('updatedAt').below(now - ttlMs).delete();
}
Or if using expiresAt:
await table.where('expiresAt').below(Date.now()).delete();
3. Schedule Cleanup Periodically
There are a few ways to trigger cleanup:
On App Start:
await cleanupExpiredData(db, 'cache', 3600 * 1000); // Clean data older than 1 hour
With setInterval:
setInterval(() =andgt; {
  cleanupExpiredData(db, 'cache', 3600 * 1000);
}, 5 * 60 * 1000); // Every 5 minutes
On Tab Visibility Change:
document.addEventListener("visibilitychange", () =andgt; {
  if (document.visibilityState === "visible") {
    cleanupExpiredData(db, 'cache', 3600 * 1000);
  }
});
4. Optional: Use an Index for expiresAt (Performance Boost)
When defining your IndexedDB schema (e.g., with Dexie.js):
db.version(1).stores({
  cache: 'id, expiresAt'
});
Then you can query efficiently with:
await db.cache.where('expiresAt').below(Date.now()).delete();
5. Add Guard on Read (to prevent use of expired records)
const item = await db.cache.get('abc123');
if (item andand item.expiresAt andlt; Date.now()) {
  await db.cache.delete(item.id);
  return null; // expired
}
return item;
Example with Dexie.js
const db = new Dexie("MyApp");
db.version(1).stores({
  cache: 'id, expiresAt'
});
async function storeItem(id, data, ttl = 3600 * 1000) {
  await db.cache.put({
    id,
    data,
    expiresAt: Date.now() + ttl
  });
}
async function cleanupTTL() {
  await db.cache.where('expiresAt').below(Date.now()).delete();
}
setInterval(cleanupTTL, 5 * 60 * 1000); // Clean every 5 mins
Summary
Step
Action
Add timestamp fields
updatedAt or expiresAt
Write cleanup logic
Use where(...).below(...).delete()
Schedule cleanup
setInterval, visibilitychange, or on startup
Guard access
Don’t return expired records
Use index
For efficient expiration queries

interview

How do you clean up stale or expired data periodically in IndexedDB (e.g., TTL)?

ICSM

Can you answer this question?

1 Answers

Strategy to Clean Stale/Expired Data in IndexedDB

1. Store Timestamps with Your Data

2. Periodic Cleanup Function

3. Schedule Cleanup Periodically

On App Start:

With `setInterval`:

On Tab Visibility Change:

4. Optional: Use an Index for `expiresAt` (Performance Boost)

5. Add Guard on Read (to prevent use of expired records)

Example with Dexie.js

Summary

Liked By

Step	Action
Add timestamp fields	`updatedAt` or `expiresAt`
Write cleanup logic	Use `where(...).below(...).delete()`
Schedule cleanup	`setInterval`, `visibilitychange`, or on startup
Guard access	Don’t return expired records
Use index	For efficient expiration queries