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

count()
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:

InvalidStateError DOMException

Thrown if this IDBObjectStore has been deleted.

TransactionInactiveError DOMException

Thrown if this IDBObjectStore's transaction is inactive.

DataError DOMException

Thrown if the specified key or key range is invalid.

Examples

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. 

const transaction = db.transaction(['fThings'], 'readonly');
const objectStore = transaction.objectStore('fThings');

const countRequest = objectStore.count();
countRequest.onsuccess = () => {
  console.log(countRequest.result);
}

Specifications

Specification
Indexed Database API 3.0
# ref-for-dom-idbobjectstore-count①

Browser compatibility

BCD tables only load in the browser

See also