IDBCursor.delete()

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The delete() method of the IDBCursor interface returns an IDBRequest object, and, in a separate thread, deletes the record at the cursor's position, without changing the cursor's position. Once the record is deleted, the cursor's value is set to null.

Be aware that you can't call delete() (or IDBCursor.update()) on cursors obtained from IDBIndex.openKeyCursor(). For such needs, you have to use IDBIndex.openCursor() instead.

Note: This feature is available in Web Workers.

Syntax

var anIDBRequest = myIDBCursor.delete();

Returns

An IDBRequest object on which subsequent events related to this operation are fired. The result attribute is set to undefined.

Exceptions

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

Exception Description
TransactionInactiveError This IDBCursor's transaction is inactive.
ReadOnlyError The transaction mode is read-only.
InvalidStateError The cursor was created using IDBindex.openKeyCursor, is currently being iterated, or has iterated past its end.
 

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. If the albumTitle of the current cursor is "Grace under pressure", we delete that entire record using  var request = cursor.delete();.

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 deleteResult() {
  list.innerHTML = '';
  var transaction = db.transaction(['rushAlbumList'], 'readwrite');
  var objectStore = transaction.objectStore('rushAlbumList');
  objectStore.openCursor().onsuccess = function(event) {
    var cursor = event.target.result;
    if(cursor) {
      if(cursor.value.albumTitle === 'Grace under pressure') {
        var request = cursor.delete();
        request.onsuccess = function() {
          console.log('Deleted that mediocre album from 1984. Even Power windows is better.');
        };
      } else {
        var listItem = document.createElement('li');
        listItem.innerHTML = '<strong>' + cursor.value.albumTitle + '</strong>, ' + cursor.value.year;
        list.appendChild(listItem);
      }
      cursor.continue();
    } else {
      console.log('Entries displayed.');
    }
  };
};
 

Specifications

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

Browser compatibility

Feature Chrome Edge Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support 23webkit
24
(Yes) 10 moz
16.0 (16.0)
10, partial 15 7.1
Available in workers (Yes) (Yes) 37.0 (37.0) ? (Yes) ?
Indexed Database 2.0 58 ? ? ? 45 ?
Feature Android Webview Chrome for Android Edge Firefox Mobile (Gecko) Firefox OS IE Phone Opera Mobile Safari Mobile
Basic support (Yes) (Yes) (Yes) 22.0 (22.0) 1.0.1 10 22 8
Available in workers (Yes) (Yes) (Yes) 37.0 (37.0) (Yes) ? (Yes) ?
Indexed Database 2.0 58 58 ? ? ? ? 45 ?

See also

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