IDBOpenDBRequest: upgradeneeded event

BaselineWidely available

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

Theupgradeneeded event is fired when an attempt was made to open a database with a version number higher than its current version.

This event is not cancelable and does not bubble.

Syntax

Use the event name in methods likeaddEventListener(), or set an event handler property.

addEventListener("upgradeneeded", (event) => { })onupgradeneeded = (event) => { }

Event type

AnIDBVersionChangeEvent. Inherits fromEvent.

Event properties

Also inherits properties from its parent,Event interface.

IDBVersionChangeEvent.oldVersionRead only: Returns the old version of the database.
IDBVersionChangeEvent.newVersionRead only: Returns the new version of the database.

Examples

This example opens a database and handles theupgradeneeded event by making any necessary updates to the object store.

// Open the databaseconst dBOpenRequest = window.indexedDB.open("toDoList", 4);dBOpenRequest.addEventListener("upgradeneeded", (event) => {  const db = event.target.result;  console.log(`Upgrading to version ${db.version}`);  // Create an objectStore for this database  const objectStore = db.createObjectStore("toDoList", {    keyPath: "taskTitle",  });  // define what data items the objectStore will contain  objectStore.createIndex("hours", "hours", { unique: false });  objectStore.createIndex("minutes", "minutes", { unique: false });  objectStore.createIndex("day", "day", { unique: false });  objectStore.createIndex("month", "month", { unique: false });  objectStore.createIndex("year", "year", { unique: false });});

This is the same example, but uses the onupgradeneeded event handler property.

// Open the databaseconst dBOpenRequest = window.indexedDB.open("toDoList", 4);dBOpenRequest.onupgradeneeded = (event) => {  const db = event.target.result;  console.log(`Upgrading to version ${db.version}`);  // Create an objectStore for this database  const objectStore = db.createObjectStore("toDoList", {    keyPath: "taskTitle",  });  // define what data items the objectStore will contain  objectStore.createIndex("hours", "hours", { unique: false });  objectStore.createIndex("minutes", "minutes", { unique: false });  objectStore.createIndex("day", "day", { unique: false });  objectStore.createIndex("month", "month", { unique: false });  objectStore.createIndex("year", "year", { unique: false });};