IDBRequest.error

The error read-only property of the IDBRequest interface returns the error in the event of an unsuccessful request.

Note: This feature is available in Web Workers.

Syntax

var myError = request.error;

Value

A DOMError containing the relevant error. In Chrome 48+/Firefox 58+ this property returns a DOMException because DOMError has been removed from the DOM standard. The following error codes are returned under certain conditions:

Error Explanation
AbortError If you abort the transaction, then all requests still in progress receive this error.
ConstraintError If you insert data that doesn't conform to a constraint. It's an exception type for creating stores and indexes. You get this error, for example, if you try to add a new key that already exists in the record.
QuotaExceededError If you run out of disk quota and the user declined to grant you more space.
UnknownError If the operation failed for reasons unrelated to the database itself. A failure due to disk IO errors is such an example.
NoError If the request succeeds.
VersionError If you try to open a database with a version lower than the one it already has.

In addition to the error codes sent to the IDBRequest object, asynchronous operations can also raise exceptions. The list describes problems that could occur when the request is being executed, but you might also encounter other problems when the request is being made. For example, if the the request failed and the result is not available, the InvalidStateError exception is thrown.

Example

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. Also included at the bottom is an onerror function that reports what the error was if the request fails. 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 do-do list with the specified 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);

  // When this new request succeeds, run the displayData()
  // function again to update the display
  updateTitleRequest.onsuccess = function() {
    displayData();
  };
};

objectStoreTitleRequest.onerror = function() {
  // If an error occurs with the request, log what it is
  console.log("There has been an error with retrieving your data: " + objectStoreTitleRequest.error);
};

Specifications

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

Browser compatibility

Update compatibility data on GitHub
DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidEdge MobileFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
Basic supportChrome Full support 24
Full support 24
No support 23 — 57
Prefixed
Prefixed Implemented with the vendor prefix: webkit
Edge Full support 12Firefox Full support 16
Full support 16
No support 10 — 16
Prefixed
Prefixed Implemented with the vendor prefix: moz
IE Full support 10
Notes
Full support 10
Notes
Notes partial
Opera 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
Edge Mobile Full support YesFirefox Android Full support 22Opera Android Full support 22Safari iOS Full support 8Samsung Internet Android Full support Yes
Full support Yes
No support ? — 7.0
Prefixed
Prefixed Implemented with the vendor prefix: webkit
DOMException value instead of DOMErrorChrome Full support 48Edge Full support YesFirefox Full support 58IE No support NoOpera Full support YesSafari No support NoWebView Android Full support 48Chrome Android Full support 48Edge Mobile Full support YesFirefox Android Full support 58Opera Android Full support YesSafari iOS No support NoSamsung Internet Android Full support 5.0

Legend

Full support  
Full support
No support  
No support
See implementation notes.
See implementation notes.
Requires a vendor prefix or different name for use.
Requires a vendor prefix or different name for use.

See also

Document Tags and Contributors

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