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The source read-only property of the IDBCursor interface returns the IDBObjectStore or IDBIndex that the cursor is iterating over. This function never returns null or throws an exception, even if the cursor is currently being iterated, has iterated past its end, or its transaction is not active.

Note: This feature is available in Web Workers.


var source = cursor.source;


The IDBObjectStore or IDBIndex that the cursor is iterating over.


In this simple fragment we create a transaction, retrieve an object store, then use a cursor to iterate through all the records in the object store. Within each iteration we log the source of the cursor, which will log our IDBobjectStore object to the console, something like this:

IDBObjectStore {autoIncrement: false, transaction: IDBTransaction, indexNames: DOMStringList, keyPath: "albumTitle", name: "rushAlbumList"…}

The cursor does not require us to select the data based on a key; we can just grab all of it. Also note that in each iteration of the loop, you can grab data from the current record under the cursor object using cursor.value.foo. For a complete working example, see our IDBCursor example (view example live.)

function displayData() {
  var transaction = db.transaction(['rushAlbumList'], "readonly");
  var objectStore = transaction.objectStore('rushAlbumList');

  objectStore.openCursor().onsuccess = function(event) {
    var cursor = event.target.result;
    if(cursor) {
      var listItem = document.createElement('li');
      listItem.innerHTML = cursor.value.albumTitle + ', ' + cursor.value.year;
    } else {
      console.log('Entries all displayed.');


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 — 24 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, arronei, libbymc, chrisdavidmills, teoli
 Last updated by: fscholz,