IDBObjectStore.clear()

Clearing an object store consists of removing all records from the object store and removing all records in indexes that reference the object store.

Syntax

var request = objectStore.clear();

Returns

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:

Example

In the following code snippet, we open a read/write transaction on our database and clear all the current data out of the object store using clear(). 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 clearData() function to clear all the data form the object store
  clearData();
};

function clearData() {
  // open a read/write db transaction, ready for clearing 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");

  // clear all the data out of the object store
  var objectStoreRequest = objectStore.clear();

  objectStoreRequest.onsuccess = function(event) {
    // report the success of our clear operation
    note.innerHTML += '<li>Data cleared.</li>';
  };
};

Specification

Browser compatibility

See also

• Using IndexedDB
• Starting transactions: IDBDatabase
• Using transactions: IDBTransaction
• Setting a range of keys: IDBKeyRange
• Retrieving and making changes to your data: IDBObjectStore
• Using cursors: IDBCursor
• Reference example: To-do Notifications (view example live.)