The source read-only property of the IDBRequest interface returns the source of the request, such as an Index or an object store. If no source exists (such as when calling, it returns null.

Note: This feature is available in Web Workers.


var IDBIndex = request.source;
var IDBCursor = request.source;
var IDBObjectStore = request.source;


An object representing the source of the request, such as an IDBIndex, IDBObjectStore or IDBCursor.


The following example requests a given record title, onsuccess gets the associated record from the IDBObjectStore (made available as objectStoreTitleRequest.result), updates one property of the record, and then puts the updated record back into the object store in another request. The source of the 2nd request is logged to the developer console. For a full working example, see our To-do Notifications app (view example live.)

var title = "Walk dog";

// Open up a transaction as usual
var objectStore = db.transaction(['toDoList'], "readwrite").objectStore('toDoList');

// Get the to-do list object that has this title as its title
var objectStoreTitleRequest = objectStore.get(title);

objectStoreTitleRequest.onsuccess = function() {
  // Grab the data object returned as the result
  var data = objectStoreTitleRequest.result;
  // Update the notified value in the object to "yes"
  data.notified = "yes";
  // Create another request that inserts the item
  // back into the database
  var updateTitleRequest = objectStore.put(data);

  // Log the source of this request
  console.log("The source of this request is " + updateTitlerequest.source);
  // When this new request succeeds, run the displayData()
  // function again to update the display 
  updateTitleRequest.onsuccess = function() { displayData(); }; 


Specification Status Comment
Indexed Database API
The definition of 'source' in that specification.
Indexed Database API 2.0
The definition of 'source' in that specification.

Browser compatibility

FeatureChromeEdgeFirefoxInternet ExplorerOperaSafari
Basic support


23 webkit



10 — 16 moz

FeatureAndroid webviewChrome for AndroidEdge mobileFirefox for AndroidOpera AndroidiOS SafariSamsung Internet
Basic support Yes Yes Yes22228 ?

1. partial

See also

Document Tags and Contributors

 Contributors to this page: fscholz, jpmedley, libbymc, chrisdavidmills, kscarfone, eicto
 Last updated by: fscholz,