IDBTransaction.error

The IDBTransaction.error property of the IDBTransaction interface returns one of several types of error when there is an unsuccessful transaction.

Note: This feature is available in Web Workers.

Syntax

var myError = transaction.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 exact error is one of serveral possibilities. It can be a reference to the same error as the request object that raised it, or a transaction failure (for example QuotaExceededError or UnknownError).

This property is null if the transaction is not finished, is finished and successfully committed, or was aborted with the IDBTransaction.abort method.

Example

In the following code snippet, we open a read/write transaction on our database and add some data to an object store. Note also the functions attached to transaction event handlers to report on the outcome of the transaction opening in the event of success or failure. Note the transaction.onerror = function(event) { }; block, making use of transaction.error to help in reporting what went wrong when the transaction was unsuccessful. For a full working example, see our To-do Notifications app (view example live.)

// Let us open our database
var DBOpenRequest = window.indexedDB.open("toDoList", 4);

DBOpenRequest.onsuccess = function(event) {
  note.innerHTML += '<li>Database initialised.</li>';
    
  // store the result of opening the database in the db variable.
  // This is used a lot below
  db = DBOpenRequest.result;
    
  // Run the addData() function to add the data to the database
  addData();
};

function addData() {
  // Create a new object ready for being inserted into the IDB
  var newItem = [ { taskTitle: "Walk dog", hours: 19, minutes: 30, day: 24, month: "December", year: 2013, notified: "no" } ];

  // open a read/write db transaction, ready for adding the data
  var transaction = db.transaction(["toDoList"], "readwrite");

  // report on the success of opening the transaction
  transaction.oncomplete = function(event) {
    note.innerHTML += '<li>Transaction completed: database modification finished.</li>';
  };


  transaction.onerror = function(event) {
    note.innerHTML += '<li>Transaction not opened due to error: ' + transaction.error + '</li>';
  };

  // create an object store on the transaction
  var objectStore = transaction.objectStore("toDoList");

  // add our newItem object to the object store
  var objectStoreRequest = objectStore.add(newItem[0]);

  objectStoreRequest.onsuccess = function(event) {
    // report the success of the request (this does not mean the item
    // has been stored successfully in the DB - for that you need transaction.onsuccess)
    note.innerHTML += '<li>Request successful.</li>';
  };
};

Specification

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 AndroidiOS SafariSamsung Internet
Basic supportChrome Full support 24
Full support 24
No support 23 — 57
Prefixed
Prefixed Requires the vendor prefix: webkit
Edge Full support 12Firefox Full support 16
Full support 16
No support 10 — 16
Prefixed
Prefixed Requires 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 Requires the vendor prefix: webkit
Chrome Android Full support 25
Full support 25
No support 25 — 57
Prefixed
Prefixed Requires 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 Requires 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, teoli
Last updated by: fscholz,