IDBObjectStore.openKeyCursor()

The openKeyCursor() method of the IDBObjectStore interface returns an IDBRequest object whose result will be set to an IDBCursor that can be used to iterate through matching results. Used for iterating through the keys of an object store with a cursor.

To determine if the add operation has completed successfully, listen for the results’s success event.

Syntax

var request = objectStore.openKeyCursor();
var request = objectStore.openKeyCursor(query);
var request = objectStore.openKeyCursor(query, direction);

Parameters

query Optional
The key range to be queried. If a single valid key is passed, this will default to a range containing only that key. If nothing is passed, this will default to a key range that selects all the records in this object store.
direction Optional
An IDBCursorDirection telling the cursor what direction to travel. Valid values are "next", "nextunique", "prev", and "prevunique". The default is "next".

Return value

An IDBRequest object on which subsequent events related to this operation are fired.

Exceptions

This method may raise a DOMException of one of the following types:

Exception Description
InvalidStateError This IDBObjectStore or IDBIndex has been deleted.
TransactionInactiveError This IDBObjectStore's transaction is inactive.
DataError The specified key or key range is invalid.

Example

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:

var transaction = db.transaction("name", "readonly");
var objectStore = transaction.objectStore("name");
var request = objectStore.openKeyCursor();
request.onsuccess = function(event) {
  var cursor = event.target.result;
  if(cursor) {
    // cursor.key contains the key of the current record being iterated through
    // note that there is no cursor.value, unlike for openCursor
    // this is where you'd do something with the result
    cursor.continue();
  } else {
    // no more results
  }
};

Specifications

Specification Status Comment
Indexed Database API 2.0
The definition of 'openKeyCursor()' in that specification.
Recommendation
Indexed Database API Draft
The definition of 'openKeyCursor()' in that specification.
Recommendation

Browser compatibility

DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
openKeyCursorChrome Full support 24
Full support 24
No support 23 — 57
Prefixed
Prefixed Implemented with the vendor prefix: webkit
Edge Full support 12Firefox Full support 44
Disabled
Full support 44
Disabled
Disabled From version 44: this feature is behind the dom.indexedDB.experimental preference. To change preferences in Firefox, visit about:config.
IE Partial support 10Opera Full support 15Safari Full support 7WebView 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 22Opera Android Full support 14Safari iOS Full support 8Samsung Internet Android Full support 1.5
Full support 1.5
No support 1.5 — 7.0
Prefixed
Prefixed Implemented with the vendor prefix: webkit

Legend

Full support
Full support
Partial support
Partial support
User must explicitly enable this feature.
User must explicitly enable this feature.
Requires a vendor prefix or different name for use.
Requires a vendor prefix or different name for use.

See also