PrimeNG p-table lazy loading request ordering under rapid concurrent interactions

Direct Answers

1. Yes, track a request token. Attach an incrementing integer or UUID to each LazyLoadEvent and discard responses whose token is older than the latest issued token. This is the only reliable way to ignore superseded results.

2. No, a shared [loading] flag is not enough. It only disables UI interaction; a late response can still mutate the table data after loading becomes false, leaving stale rows visible.

3. multiSortMeta is stable from PrimeNG 6.x onward. Earlier major versions either lack the property or use a different API. Confirm your installed major version before relying on it.

Why the Token Pattern Works

PrimeNG fires onLazyLoad for every sort, page, or filter change without built-in debouncing or cancellation. Network latency can reorder responses. A monotonically increasing token (e.g., this.requestId++) attached to the outgoing request lets the callback compare event.requestId === this.currentRequestId before applying data. Older responses fail the check and are ignored.

Minimal Implementation Steps

1. Add a private requestId = 0 counter in the component.
2. In onLazyLoad(event), increment this.requestId and assign event.requestId = this.requestId.
3. Pass the token to your data service; include it in the API call if the backend echoes it, or keep it client-side only.
4. When the response arrives, verify response.requestId === this.requestId before updating this.rows or this.totalRecords.
5. Set [loading] independently for UX feedback; do not rely on it for correctness.

Version Check Required

Run npm list @primeng/prime-ng (or check package.json) to confirm the major version. If you are on PrimeNG 5.x or earlier, multiSortMeta may be absent or named differently; adjust the sort-handling logic accordingly.

One Diagnostic Needed

What is the exact PrimeNG major version in package.json? This determines whether multiSortMeta can be used safely.