IDBObjectStore: keyPath property

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.

Learn more
See full compatibility

Note: This feature is available in Web Workers.

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.

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
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.keyPath);
 // 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.";
 };
}