IDBOpenDBRequest Redirect 1

« IDBOpenDBRequest

The IDBOpenDBRequest interface of the IndexedDB API provides access to results of requests to open databases using specific event handler attributes.

Inherits from: IDBRequest


No methods.


Event handlers

The event handler for the blocked event. This event is triggered when the upgradeneeded should be triggered because of a version change but the database is still in use (ie not closed) somewhere, even after the versionchange event was sent.
The event handler for the upgradeneeded event, fired when a database of a bigger version number than the existing stored database is loaded.

Derived interface

No derived interface


var db;

// Let us open our database
var request ="toDoList", 4);

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

request.onsuccess = function(event) {
  note.innerHTML += '<li>Database initialised.</li>';
  // store the result of opening the database in the db variable. This is used a lot below
  db = request.result;
  // Run the displayData() function to populate the task list with all the to-do list data already in the IDB

// This event handles the event whereby a new version of the database needs to be created
// Either one has not been created before, or a new version number has been submitted via the
// line above
//it is only implemented in recent browsers
request.onupgradeneeded = function(event) {
  var db =;
  db.onerror = function(event) {
    note.innerHTML += '<li>Error loading database.</li>';

  // Create an objectStore for this database   
  var objectStore = db.createObjectStore("toDoList", { keyPath: "taskTitle" });


Specification Status Comment
Indexed Database API Candidate Recommendation  

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support



11.0 (11.0)moz

16.0 (16.0)

10 17 Not supported
Feature Android Chrome Mobile Firefox Mobile (Gecko) Firefox OS IE Phone Opera Mobile Safari Mobile
Basic support 4.4 Yeswebkit 6.0 (6.0) 1.0.1 10 17 Not supported

See also

  • Using IndexedDB
  • The reference application for the examples in this reference: To-do Notifications (view example live.) Not every snippet appears in this example, but every example uses the same data structure and syntax, and they will make sense in the context of this example.

Document Tags and Contributors

 Last updated by: teoli,