Web/API/IDBRequest

The IDBRequest interface of the IndexedDB API provides access to results of asynchronous requests to databases and database objects using event handler attributes. Each reading and writing operation on a database is done using a request.

The request object does not initially contain any information about the result of the operation, but once information becomes available, an event is fired on the request, and the information becomes available through the properties of the IDBRequest instance.

All asynchronous operations immediately return an IDBRequest instance. Each request has a readyState that is set to the 'pending' state; this changes to 'done' when the request is completed or fails. When the state is set to done, every request returns a result and an error, and an event is fired on the request. When the state is still pending, any attempt to access the result or error raises an InvalidStateError exception.

In plain words, all asynchronous methods return a request object. If the request has been completed successfully, the result is made available through the result property and an event indicating success is fired at the request (IDBRequest.onsuccess). If an error occurs while performing the operation, the exception is made available through the result property and an error event is fired (IDBRequest.onerror).

The interface IDBOpenDBRequest is derived from IDBRequest.

Note: This feature is available in Web Workers.

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Properties

Also inherits properties from EventTarget.

IDBRequest.error Read only: Returns a DOMException in the event of an unsuccessful request, indicating what went wrong.
IDBRequest.result Read only: Returns the result of the request. If the the request failed and the result is not available, an InvalidStateError exception is thrown.
IDBRequest.source Read only: The source of the request, such as an IDBIndex or an IDBObjectStore. If no source exists (such as when calling IDBFactory.open), it returns null.
IDBRequest.readyState Read only: The state of the request. Every request starts in the pending state. The state changes to done when the request completes successfully or when an error occurs.
IDBRequest.transaction Read only: The transaction for the request. This property can be null for certain requests, for example those returned from IDBFactory.open unless an upgrade is needed. (You're just connecting to a database, so there is no transaction to return).

Methods

No methods, but inherits methods from EventTarget.

Events

Listen to these events using addEventListener() or by assigning an event listener to the oneventname property of this interface.

error: Fired when an error caused a request to fail. Also available via the onerror property.
success: Fired when an IDBRequest succeeds. Also available via the onsuccess property.

Example

In the following code snippet, we open a database asynchronously and make a request; onerror and onsuccess functions are included to handle the success and error cases. For a full working example, see our To-do Notifications app (view example live.)

var db;

// Let us open our database
var DBOpenRequest = window.indexedDB.open("toDoList", 4);

// these two event handlers act on the database being
// opened successfully, or not
DBOpenRequest.onerror = function(event) {
  note.innerHTML += '<li>Error loading database.</li>';
};

DBOpenRequest.onsuccess = function(event) {
  note.innerHTML += '<li>Database initialised.</li>';
 
  // store the result of opening the database.
  db = DBOpenRequest.result;
};

Specifications

Specification	Status	Comment
Indexed Database API 2.0The definition of 'IDBRequest' in that specification.	Recommendation	Initial definition.
Indexed Database API DraftThe definition of 'IDBRequest' in that specification.	Recommendation

Browser compatibility

Update compatibility data on GitHub

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
`IDBRequest`	Chrome Full support 24 Full support 24 No support 2 — 57 Prefixed' Prefixed' Implemented with the vendor prefix: webkit	Edge Full support 12	Firefox Full support 16 Full support 16 No support 10 — 16 Prefixed' Prefixed' Implemented with the vendor prefix: moz	IE Partial support 10	Opera Full support 15	Safari Full support 7	WebView Android Full support Yes Full support Yes No support ? — 57 Prefixed' Prefixed' Implemented with the vendor prefix: webkit	Chrome Android Full support 25 Full support 25 No support 25 — 57 Prefixed' Prefixed' Implemented with the vendor prefix: webkit	Firefox Android Full support 22	Opera Android Full support 14	Safari iOS Full support 8	Samsung Internet Android Full support 1.5 Full support 1.5 No support 1.5 — 7.0 Prefixed' Prefixed' Implemented with the vendor prefix: webkit
`error`	Chrome Full support 24 Full support 24 No support 23 — 57 Prefixed' Prefixed' Implemented with the vendor prefix: webkit	Edge Full support 12	Firefox Full support 16 Full support 16 No support 10 — 16 Prefixed' Prefixed' Implemented with the vendor prefix: moz	IE Partial support 10	Opera Full support 15	Safari Full support 7	WebView Android Full support Yes Full support Yes No support ? — 57 Prefixed' Prefixed' Implemented with the vendor prefix: webkit	Chrome Android Full support 25 Full support 25 No support 25 — 57 Prefixed' Prefixed' Implemented with the vendor prefix: webkit	Firefox Android Full support 22	Opera Android Full support 14	Safari iOS Full support 8	Samsung Internet Android Full support 1.5 Full support 1.5 No support 1.5 — 7.0 Prefixed' Prefixed' Implemented with the vendor prefix: webkit
`error` event	Chrome Full support 24 Full support 24 Full support 23 Prefixed' Prefixed' Implemented with the vendor prefix: webkit	Edge Full support 12	Firefox Full support 16 Full support 16 No support 10 — 16 Prefixed' Prefixed' Implemented with the vendor prefix: moz	IE Partial support 10	Opera Full support 15	Safari Full support 7	WebView Android Full support Yes	Chrome Android Full support Yes	Firefox Android Full support 22	Opera Android Full support 14	Safari iOS Full support 8	Samsung Internet Android Full support Yes
`onerror`	Chrome Full support 24 Full support 24 Full support 23 Prefixed' Prefixed' Implemented with the vendor prefix: webkit	Edge Full support 12	Firefox Full support 16 Full support 16 No support 10 — 16 Prefixed' Prefixed' Implemented with the vendor prefix: moz	IE Partial support 10	Opera Full support 15	Safari Full support 7	WebView Android Full support Yes	Chrome Android Full support Yes	Firefox Android Full support 22	Opera Android Full support 14	Safari iOS Full support 8	Samsung Internet Android Full support Yes
`onsuccess`	Chrome Full support 24 Full support 24 Full support 23 Prefixed' Prefixed' Implemented with the vendor prefix: webkit	Edge Full support 12	Firefox Full support 16 Full support 16 No support 10 — 16 Prefixed' Prefixed' Implemented with the vendor prefix: moz	IE Partial support 10	Opera Full support 15	Safari Full support 7	WebView Android Full support Yes	Chrome Android Full support Yes	Firefox Android Full support 22	Opera Android Full support 14	Safari iOS Full support 8	Samsung Internet Android Full support Yes
`readyState`	Chrome Full support 24 Full support 24 Full support 23 Prefixed' Prefixed' Implemented with the vendor prefix: webkit	Edge Full support 12	Firefox Full support 16 Full support 16 No support 10 — 16 Prefixed' Prefixed' Implemented with the vendor prefix: moz	IE Partial support 10	Opera Full support 15	Safari Full support 7	WebView Android Full support Yes	Chrome Android Full support Yes	Firefox Android Full support 22	Opera Android Full support 14	Safari iOS Full support 8	Samsung Internet Android Full support Yes
`result`	Chrome Full support 24 Full support 24 Full support 23 Prefixed' Prefixed' Implemented with the vendor prefix: webkit	Edge Full support 12	Firefox Full support 16 Full support 16 No support 10 — 16 Prefixed' Prefixed' Implemented with the vendor prefix: moz	IE Partial support 10	Opera Full support 15	Safari Full support 7	WebView Android Full support Yes	Chrome Android Full support Yes	Firefox Android Full support 22	Opera Android Full support 14	Safari iOS Full support 8	Samsung Internet Android Full support Yes
`source`	Chrome Full support 24 Full support 24 Full support 23 Prefixed' Prefixed' Implemented with the vendor prefix: webkit	Edge Full support 12	Firefox Full support 16 Full support 16 No support 10 — 16 Prefixed' Prefixed' Implemented with the vendor prefix: moz	IE Partial support 10	Opera Full support 15	Safari Full support 7	WebView Android Full support Yes	Chrome Android Full support Yes	Firefox Android Full support 22	Opera Android Full support 14	Safari iOS Full support 8	Samsung Internet Android Full support Yes
`success` event	Chrome Full support 24 Full support 24 Full support 23 Prefixed' Prefixed' Implemented with the vendor prefix: webkit	Edge Full support 12	Firefox Full support 16 Full support 16 No support 10 — 16 Prefixed' Prefixed' Implemented with the vendor prefix: moz	IE Partial support 10	Opera Full support 15	Safari Full support 7	WebView Android Full support Yes	Chrome Android Full support Yes	Firefox Android Full support 22	Opera Android Full support 14	Safari iOS Full support 8	Samsung Internet Android Full support Yes
`transaction`	Chrome Full support 24 Full support 24 Full support 23 Prefixed' Prefixed' Implemented with the vendor prefix: webkit	Edge Full support 12	Firefox Full support 16 Full support 16 No support 10 — 16 Prefixed' Prefixed' Implemented with the vendor prefix: moz	IE Partial support 10	Opera Full support 15	Safari Full support 7	WebView Android Full support Yes	Chrome Android Full support Yes	Firefox Android Full support 22	Opera Android Full support 14	Safari iOS Full support 8	Samsung Internet Android Full support Yes
Available in workers	Chrome Full support Yes	Edge Full support ≤79	Firefox Full support 37	IE ?	Opera Full support Yes	Safari ?	WebView Android Full support Yes	Chrome Android Full support Yes	Firefox Android Full support 37	Opera Android Full support Yes	Safari iOS ?	Samsung Internet Android Full support Yes

Legend

Full support: Full support
Partial support: Partial support
Compatibility unknown: Compatibility unknown
Requires a vendor prefix or different name for use.': Requires a vendor prefix or different name for use.