IDBObjectStore.keyPath

The keyPath read-only property of the IDBObjectStore interface returns the key path of this object store.

If this property is null, the application must provide a key for each modification operation.

Note:

This feature is available in Web Workers.

Syntax

var mykeyPath = objectStore.keyPath;

Value

Any value type.

Example

In the following code snippet, we open a read/write transaction on our database and add some data to an object store using add(). After the object store has been created, we log objectStore.keyPath to the console. 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 to insert 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 the transaction completing, when everything is done
  transaction.oncomplete = function(event) {
    note.innerHTML += '<li>Transaction completed.</li>';
  };

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

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

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

  objectStoreRequest.onsuccess = function(event) {
    // report the success of our request
    note.innerHTML += '<li>Request successful.</li>';
  };
};

Specifications

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

Browser compatibility

BCD tables only load in the browser

See also