The name property of the IDBIndex interface contains a string which names the index.

A string specifying a name for the index.

There are a several exceptions that can occur when you attempt to change an index's name.

InvalidStateError DOMException

Thrown if the index, or its object store, has been deleted or if the current transaction is not an upgrade transaction. You can only rename indexes during upgrade transactions; that is, when the mode is "versionchange".

TransactionInactiveError DOMException

Thrown if the current transaction is not active.

ConstraintError DOMException

Thrown if an index is already using the specified name.

In the following example we open a transaction and an object store, then get the index lName from a simple contacts database. We then open a basic cursor on the index using IDBIndex.openCursor() — this works the same as opening a cursor directly on an IDBObjectStore using openCursor() except that the returned records are sorted based on the index, not the primary key.

The name of the index is logged to the console: it should be returned as lName.

Finally, we iterate through each record, inserting the data into an HTML table. For a complete working example, see our IndexedDB-examples demo repo (View the example live).

function displayDataByIndex() {
  tableEntry.innerHTML = "";
  const transaction = db.transaction(["contactsList"], "readonly");
  const objectStore = transaction.objectStore("contactsList");

  const myIndex = objectStore.index("lName");
  console.log(myIndex.name);

  myIndex.openCursor().onsuccess = (event) => {
    const cursor = event.target.result;
    if (cursor) {
      const tableRow = document.createElement("tr");
      tableRow.innerHTML =
        `<td>${cursor.value.id}</td>` +
        `<td>${cursor.value.lName}</td>` +
        `<td>${cursor.value.fName}</td>` +
        `<td>${cursor.value.jTitle}</td>` +
        `<td>${cursor.value.company}</td>` +
        `<td>${cursor.value.eMail}</td>` +
        `<td>${cursor.value.phone}</td>` +
        `<td>${cursor.value.age}</td>`;
      tableEntry.appendChild(tableRow);

      cursor.continue();
    } else {
      console.log("Entries all displayed.");
    }
  };
}

• Using IndexedDB
• Starting transactions: IDBDatabase
• Using transactions: IDBTransaction
• Setting a range of keys: IDBKeyRange
• Retrieving and making changes to your data: IDBObjectStore
• Using cursors: IDBCursor
• Reference example: To-do Notifications (View the example live).