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IDBOpenDBRequest: upgradeneeded event

files/en-us/web/api/idbopendbrequest/upgradeneeded_event/index.md

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{{APIRef("IndexedDB")}}

The upgradeneeded 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 like {{domxref("EventTarget.addEventListener", "addEventListener()")}}, or set an event handler property.

js-nolint
addEventListener("upgradeneeded", (event) => { })

onupgradeneeded = (event) => { }

Event type

An {{domxref("IDBVersionChangeEvent")}}. Inherits from {{domxref("Event")}}.

{{InheritanceDiagram("IDBVersionChangeEvent")}}

Event properties

Also inherits properties from its parent, {{domxref("Event")}} interface.

  • {{ domxref("IDBVersionChangeEvent.oldVersion") }} {{ReadOnlyInline}}
    • : Returns the old version of the database.
  • {{ domxref("IDBVersionChangeEvent.newVersion") }} {{ReadOnlyInline}}
    • : Returns the new version of the database.

Examples

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

js
// Open the database
const 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.

js
// Open the database
const 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 });
};

Specifications

{{Specifications}}

Browser compatibility

{{Compat}}

See also