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.
var request = ObjectStore.count(); var request = ObjectStore.count(query);
IDBKeyRange
object that specifies a range of records you want to count.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:
Exception | Description |
---|---|
InvalidStateError | This IDBObjectStore has been deleted. |
TransactionInactiveError | This IDBObjectStore 's transaction is inactive. |
DataError | 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); }
Specification | Status | Comment |
---|---|---|
Indexed Database API The definition of 'count()' in that specification. | Recommendation | |
Indexed Database API 2.0 The definition of 'count()' in that specification. | Recommendation |
Desktop | ||||||
---|---|---|---|---|---|---|
Chrome | Edge | Firefox | Internet Explorer | Opera | Safari | |
Basic support | 24
|
12 | 16
|
10
|
15 | 7 |
Mobile | |||||||
---|---|---|---|---|---|---|---|
Android webview | Chrome for Android | Edge Mobile | Firefox for Android | Opera for Android | iOS Safari | Samsung Internet | |
Basic support | Yes
|
25
|
Yes | 22 | 22 | 8 | Yes
|
IDBDatabase
IDBTransaction
IDBKeyRange
IDBObjectStore
IDBCursor
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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/IDBObjectStore/count