IDBDatabase
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.
Note: This feature is available inWeb Workers.
TheIDBDatabase interface of the IndexedDB API provides aconnection to a database; you can use anIDBDatabase object to open atransaction on your database then create, manipulate, and delete objects (data) in that database. The interface provides the only way to get and manage versions of the database.
Note:Everything you do in IndexedDB always happens in the context of atransaction, representing interactions with data in the database. All objects in IndexedDB — including object stores, indexes, and cursors — are tied to a particular transaction. Thus, you cannot execute commands, access data, or open anything outside of a transaction.
In this article
Instance properties
IDBDatabase.nameRead onlyA string that contains the name of the connected database.
IDBDatabase.versionRead onlyA 64-bit integer that contains the version of the connected database. When a database is first created, this attribute is an empty string.
IDBDatabase.objectStoreNamesRead onlyA
DOMStringListthat contains a list of the names of theobject stores currently in the connected database.
Instance methods
Inherits from:EventTarget
IDBDatabase.close()Returns immediately and closes the connection to a database in a separate thread.
IDBDatabase.createObjectStore()Creates and returns a new object store or index.
IDBDatabase.deleteObjectStore()Destroys the object store with the given name in the connected database, along with any indexes that reference it.
IDBDatabase.transaction()Immediately returns a transaction object (
IDBTransaction) containing theIDBTransaction.objectStoremethod, which you can use to access your object store. Runs in a separate thread.
Events
Listen to these events usingaddEventListener() or by assigning an event listener to theoneventname property of this interface.
closeAn event fired when the database connection is unexpectedly closed.
versionchangeAn event fired when a database structure change was requested.
The following events are available toIDBDatabase via event bubbling fromIDBTransaction:
Example
In the following code snippet, we open a database asynchronously (IDBFactory), handle success and error cases, and create a new object store in the case that an upgrade is needed (IDBDatabase). For a complete working example, see ourTo-do Notifications app (view example live).
// Let us open our databaseconst DBOpenRequest = window.indexedDB.open("toDoList", 4);// these two event handlers act on the IDBDatabase object,// when the database is opened successfully, or notDBOpenRequest.onerror = (event) => { note.appendChild(document.createElement("li")).textContent = "Error loading database.";};DBOpenRequest.onsuccess = (event) => { node.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 db = DBOpenRequest.result; // Run the displayData() function to populate the task // list with all the to-do list data already in the IDB displayData();};// This event handles the event whereby a new version of// the database needs to be created Either one has not// been created before, or a new version number has been// submitted via the window.indexedDB.open line aboveDBOpenRequest.onupgradeneeded = (event) => { const db = event.target.result; db.onerror = (event) => { note.appendChild(document.createElement("li")).textContent = "Error loading database."; }; // Create an objectStore for this database using // IDBDatabase.createObjectStore 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 }); objectStore.createIndex("notified", "notified", { unique: false }); note.appendChild(document.createElement("li")).textContent = "Object store created.";};This next line opens up a transaction on the Database, then opens an object store that we can then manipulate the data inside of.
const objectStore = db .transaction("toDoList", "readwrite") .objectStore("toDoList");Specifications
| Specification |
|---|
| Indexed Database API 3.0> # database-interface> |
Browser compatibility
See also
- Using IndexedDB
- 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).