IDBObjectStore.get()

The get() method of the IDBObjectStore interface returns an IDBRequest object, and, in a separate thread, returns the object store selected by the specified key. This is for retrieving specific records from an object store.

If a value is successfully found, then a structured clone of it is created and set as the result of the request object.

Note: This method produces the same result for: a) a record that doesn't exist in the database and b) a record that has an undefined value. To tell these situations apart, call the openCursor() method with the same key. That method provides a cursor if the record exists, and no cursor if it does not.

Note: This feature is available in Web Workers.

Syntax

var request = objectStore.get(myItem);

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:

Exception Description
TransactionInactiveError This IDBObjectStore's transaction is inactive.
DataError

The key or key range provided contains an invalid key.

InvalidStateError The IDBObjectStore has been deleted or removed.
 

Example

In the following code snippet, we open a read/write transaction on our database and get one specific record from object store using get() — a sample record with the key "Walk dog". Once this data object is retrieved, you could then update it using normal JavaScript, then put it back into the database using  a IDBObjectStore.put operation. 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 getData() function to get the data from the database
  getData();
};

function getData() {
  // open a read/write db transaction, ready for retrieving 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.get("Walk dog");

  objectStoreRequest.onsuccess = function(event) {
    // report the success of our get operation
    note.innerHTML += '<li>Record retrieved.</li>';

    var myRecord = objectStoreRequest.result;
  };

};

Parameters

key
The key or key range that identifies the record to be retrieved.

Specifications

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

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support 23webkit
24
10 moz
16.0 (16.0)
10, partial 15 7.1
Available in workers (Yes) 37.0 (37.0) ? (Yes) ?
Feature Android Firefox Mobile (Gecko) Firefox OS IE Phone Opera Mobile Safari Mobile
Basic support 4.4 22.0 (22.0) 1.0.1 10 22 8
Available in workers (Yes) 37.0 (37.0) (Yes) ? (Yes) ?

See also

Document Tags and Contributors

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