IDBObjectStore: autoIncrement property

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since ⁨January 2020⁩.

Note: This feature is available in Web Workers.

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.

Value

A boolean value:

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

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.appendChild(document.createElement("li")).textContent =     "Database initialized.";    // 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.appendChild(document.createElement("li")).textContent =       "Transaction completed.";   };    transaction.onerror = (event) => {     note.appendChild(document.createElement("li")).textContent =       "Transaction not opened due to error. Duplicate items not allowed.";   };    // 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.appendChild(document.createElement("li")).textContent =       "Request successful.";   }; }