IDBVersionChangeEvent: newVersion property

const note = document.querySelector("ul");
// Let us open version 4 of our database
const DBOpenRequest = window.indexedDB.open("toDoList", 4);
// these two event handlers act on the database being opened
DBOpenRequest.onerror = (event) => {
  note.appendChild(document.createElement("li")).textContent =
    "Error loading database.";
};
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 later on, for opening transactions and suchlike.
  const db = DBOpenRequest.result;
};