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