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IDBObjectStore.count

The count() method of the IDBObjectStore interface returns an IDBRequest object, and, in a separate thread, returns the total number of records that match the provided key or IDBKeyRange. If no arguments are provided, it returns the total number of records in the store.

Note: This feature is available in Web Workers.

Syntax

var request = ObjectStore.count();
var request = ObjectStore.count(query);

Parameters

query Optional
A key or IDBKeyRange object that specifies a range of records you want to count.

Return value

An IDBRequest object on which subsequent events related to this operation are fired.

Exceptions

This method may raise a DOMException of one of the following types:

Exception Description
InvalidStateError This IDBObjectStore has been deleted.
TransactionInactiveError This IDBObjectStore's transaction is inactive.
DataError The specified key or key range is invalid.

Example

In this simple fragment we create a transaction, retrieve an object store, then count the number of records in the store using count() — when the success handler fires, we log the count value (an integer) to the console.

var transaction = db.transaction(['fThings'], 'readonly');
var objectStore = transaction.objectStore('fThings');
    
var countRequest = objectStore.count();
countRequest.onsuccess = function() {
  console.log(countRequest.result);
}

Specification

Browser compatibilityUpdate compatibility data on GitHub

Desktop
Chrome Edge Firefox Internet Explorer Opera Safari
Basic support 24
24
23 — 57
Prefixed
Prefixed Requires the vendor prefix: webkit
12 16
16
10 — 16
Prefixed
Prefixed Requires the vendor prefix: moz
10
10
partial
15 7
Mobile
Android webview Chrome for Android Edge Mobile Firefox for Android Opera for Android iOS Safari Samsung Internet
Basic support Yes
Yes
? — 57
Prefixed
Prefixed Requires the vendor prefix: webkit
25
25
25 — 57
Prefixed
Prefixed Requires the vendor prefix: webkit
Yes 22 22 8 Yes
Yes
? — 7.0
Prefixed
Prefixed Requires the vendor prefix: webkit

See also

© 2005–2018 Mozilla Developer Network and individual contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/IDBObjectStore/count