IDBFactory.open()
The open()
method of the IDBFactory
interface requests opening a connection to a database.
The method returns an IDBOpenDBRequest
object immediately, and
performs the open operation asynchronously. If the operation is successful, a
success
event is fired on the request object that is returned from this
method, with its result
attribute set to the new
IDBDatabase
object for the connection.
May trigger upgradeneeded
, blocked
or
versionchange
events.
Note: This feature is available in Web Workers
Syntax
For the current standard:
var IDBOpenDBRequest = indexedDB.open(name);
var IDBOpenDBRequest = indexedDB.open(name, version);
Parameters
- name
-
The name of the database.
- version Optional
-
Optional. The version to open the database with. If the version is not provided and the database exists, then a connection to the database will be opened without changing its version. If the version is not provided and the database does not exist, then it will be created with version
1
.
Experimental Gecko options object
- options (version and storage) Optional
-
In Gecko, since version 26, you can include a non-standard
options
object as a parameter ofIDBFactory.open
that contains theversion
number of the database, plus a storage value that specifies whether you want to usepersistent
ortemporary
storage.Warning: The
storage
attribute is deprecated and will soon be removed from Gecko. You should useStorageManager.persist()
to get persistent storage instead.
Note: You can find out more information on the different available storage types, and how Firefox handles client-side data storage, at Browser storage limits and eviction criteria.
Return value
A IDBOpenDBRequest
object on which subsequent events related to this
request are fired.
Exceptions
This method may raise a DOMException
of the following types:
Exception | Description |
---|---|
TypeError |
The value of version is zero or a negative number or not a number. |
Example
Example of calling open
with the current specification's
version
parameter:
var request = window.indexedDB.open("toDoList", 4);
In the following code snippet, we make a request to open a database, and include handlers for the success and error cases. For a full working example, see our To-do Notifications app (view example live.)
var note = document.querySelector("ul");
// In the following line, you should include the prefixes
// of implementations you want to test.
window.indexedDB = window.indexedDB || window.mozIndexedDB || window.webkitIndexedDB || window.msIndexedDB;
// DON'T use "var indexedDB = ..." if you're not in a function.
// Moreover, you may need references to some window.IDB* objects:
window.IDBTransaction = window.IDBTransaction || window.webkitIDBTransaction || window.msIDBTransaction;
window.IDBKeyRange = window.IDBKeyRange || window.webkitIDBKeyRange || window.msIDBKeyRange;
// (Mozilla has never prefixed these objects, so we don't
// need window.mozIDB*)
// Let us open version 4 of our database
var DBOpenRequest = window.indexedDB.open("toDoList", 4);
// these two event handlers act on the database being opened
// successfully, or not
DBOpenRequest.onerror = function(event) {
note.innerHTML += '<li>Error loading database.</li>';
};
DBOpenRequest.onsuccess = function(event) {
note.innerHTML += '<li>Database initialized.</li>';
// store the result of opening the database in the db
// variable. This is used a lot later on, for opening
// transactions and suchlike.
db = DBOpenRequest.result;
};
Specifications
Specification |
---|
Indexed Database API 3.0 # ref-for-dom-idbfactory-open② |
Browser compatibility
BCD tables only load in the browser
See also
- 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 example live.)