Web/API/IDBRequest/error event

The error handler is executed when an error caused a request to fail.

Bubbles	Yes
Cancelable	No
Interface	Event
Event handler property	onerror

Examples

This example opens a database and tries to add a record, listening for the error event for the add() operation (this will occur if, for example, a record with the given taskTitle already exists):

// Open the database
const DBOpenRequest = window.indexedDB.open('toDoList', 4);

DBOpenRequest.addEventListener('upgradeneeded', event => {
  const db = event.target.result;

  db.onerror = () => {
    console.log('Error creating database');
  };

  // Create an objectStore for this database
  var objectStore = db.createObjectStore('toDoList', { keyPath: 'taskTitle' });

  // define what data items the objectStore will contain
  objectStore.createIndex('hours', 'hours', { unique: false });
  objectStore.createIndex('minutes', 'minutes', { unique: false });
  objectStore.createIndex('day', 'day', { unique: false });
  objectStore.createIndex('month', 'month', { unique: false });
  objectStore.createIndex('year', 'year', { unique: false });
});

DBOpenRequest.addEventListener('success', event => {
  const db = DBOpenRequest.result;

  // open a read/write db transaction, ready for adding the data
  const transaction = db.transaction(['toDoList'], 'readwrite');
  const objectStore = transaction.objectStore('toDoList');
  const newItem = { taskTitle: 'my task', hours: 10, minutes: 10, day: 10, month: 'January', year: 2020 };

  const objectStoreRequest = objectStore.add(newItem);
  objectStoreRequest.addEventListener('error', () => {
    console.log(`Error adding new item: ${newItem.taskTitle}`);
  });
});

The same example, using the onerror property instead of addEventListener():

// Open the database
const DBOpenRequest = window.indexedDB.open('toDoList', 4);

DBOpenRequest.onupgradeneeded = event => {
  const db = event.target.result;

  db.onerror = () => {
    console.log('Error creating database');
  };

  // Create an objectStore for this database
  var objectStore = db.createObjectStore('toDoList', { keyPath: 'taskTitle' });

  // define what data items the objectStore will contain
  objectStore.createIndex('hours', 'hours', { unique: false });
  objectStore.createIndex('minutes', 'minutes', { unique: false });
  objectStore.createIndex('day', 'day', { unique: false });
  objectStore.createIndex('month', 'month', { unique: false });
  objectStore.createIndex('year', 'year', { unique: false });
};

DBOpenRequest.onsuccess = event => {
  const db = DBOpenRequest.result;

  // open a read/write db transaction, ready for adding the data
  const transaction = db.transaction(['toDoList'], 'readwrite');
  const objectStore = transaction.objectStore('toDoList');
  const newItem = { taskTitle: 'my task', hours: 10, minutes: 10, day: 10, month: 'January', year: 2020 };

  const objectStoreRequest = objectStore.add(newItem);
  objectStoreRequest.onerror = () => {
    console.log(`Error adding new item: ${newItem.taskTitle}`);
  };
};

Browser compatibility

The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.

Update compatibility data on GitHub

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
error event	Chrome Full support 24 Full support 24 Full support 23 Prefixed' Prefixed' Implemented with the vendor prefix: webkit	Edge Full support 12	Firefox Full support 16 Full support 16 No support 10 — 16 Prefixed' Prefixed' Implemented with the vendor prefix: moz	IE Partial support 10	Opera Full support 15	Safari Full support 7	WebView Android Full support Yes	Chrome Android Full support Yes	Firefox Android Full support 22	Opera Android Full support 14	Safari iOS Full support 8	Samsung Internet Android Full support Yes

Legend

Full support  

Full support

Partial support  

Partial support

Requires a vendor prefix or different name for use.'

Requires a vendor prefix or different name for use.

See also

• Using IndexedDB
• onerror event handler property

IDBRequest: error event by Mozilla Contributors is licensed under CC-BY-SA 2.5.