IDBObjectStore: autoIncrement property

The autoIncrement read-only property of the IDBObjectStore interface returns the value of the auto increment flag for this object store.

Note that every object store has its own separate auto increment counter.

Note: This feature is available in Web Workers

Value

A boolean value:

Value Meaning
true The object store auto increments.
false The object store does not auto increment.

Examples

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.autoIncrement to the console. For a full working example, see our To-do Notifications app (view example live). 

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

DBOpenRequest.onsuccess = (event) => {
  note.innerHTML += "<li>Database initialized.</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
  const 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
  const transaction = db.transaction(["toDoList"], "readwrite");

  // report on the success of the transaction completing, when everything is done
  transaction.oncomplete = (event) => {
    note.innerHTML += "<li>Transaction completed.</li>";
  };

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

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

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

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

Specifications

Specification
Indexed Database API 3.0
# ref-for-dom-idbobjectstore-autoincrement①

Browser compatibility

BCD tables only load in the browser

See also