The get()
method of the IDBObjectStore
interface returns an IDBRequest
object, and, in a separate thread, returns the object store selected by the specified key. This is for retrieving specific records from an object store.
If a value is successfully found, then a structured clone of it is created and set as the result
of the request object.
openCursor()
method with the same key. That method provides a cursor if the record exists, and no cursor if it does not.Syntax
var request = objectStore.get(key);
Parameters
- key
- The key or key range that identifies the record to be retrieved.
Return value
An IDBRequest
object on which subsequent events related to this operation are fired.
Exceptions
This method may raise a DOMException
of one of the following types:
Exception | Description |
---|---|
TransactionInactiveError | This IDBObjectStore 's transaction is inactive. |
DataError |
The key or key range provided contains an invalid key. |
InvalidStateError |
The IDBObjectStore has been deleted or removed. |
Example
In the following code snippet, we open a read/write transaction on our database and get one specific record from object store using get()
— a sample record with the key "Walk dog". Once this data object is retrieved, you could then update it using normal JavaScript, then put it back into the database using a IDBObjectStore.put
operation. For a full working example, see our To-do Notifications app (view example live.)
// Let us open our database var DBOpenRequest = window.indexedDB.open("toDoList", 4); DBOpenRequest.onsuccess = function(event) { note.innerHTML += '<li>Database initialised.</li>'; // store the result of opening the database in the db variable. // This is used a lot below db = DBOpenRequest.result; // Run the getData() function to get the data from the database getData(); }; function getData() { // open a read/write db transaction, ready for retrieving the data var transaction = db.transaction(["toDoList"], "readwrite"); // report on the success of the transaction completing, when everything is done transaction.oncomplete = function(event) { note.innerHTML += '<li>Transaction completed.</li>'; }; transaction.onerror = function(event) { note.innerHTML += '<li>Transaction not opened due to error: ' + transaction.error + '</li>'; }; // create an object store on the transaction var objectStore = transaction.objectStore("toDoList"); // Make a request to get a record by key from the object store var objectStoreRequest = objectStore.get("Walk dog"); objectStoreRequest.onsuccess = function(event) { // report the success of our request note.innerHTML += '<li>Request successful.</li>'; var myRecord = objectStoreRequest.result; }; };
Specifications
Specification | Status | Comment |
---|---|---|
Indexed Database API The definition of 'get()' in that specification. |
Recommendation | |
Indexed Database API 2.0 The definition of 'get()' in that specification. |
Editor's Draft |
Browser compatibility
Feature | Chrome | Edge | Firefox (Gecko) | Internet Explorer | Opera | Safari (WebKit) |
---|---|---|---|---|---|---|
Basic support | 23webkit 24 (unprefixed) |
(Yes) | 10 moz 16.0 (16.0) |
10, partial | 15 | 7.1 |
Available in workers | (Yes) | ? | 37.0 (37.0) | ? | (Yes) | ? |
Indexed Database 2.0 | 58 | ? | ? | ? | 45 | ? |
Feature | Android Webview | Chrome for Android | Edge | Firefox Mobile (Gecko) | Firefox OS | IE Phone | Opera Mobile | Safari Mobile |
---|---|---|---|---|---|---|---|---|
Basic support | (Yes) | (Yes) | (Yes) | 22.0 (22.0) | 1.0.1 | 10 | 22 | 8 |
Available in workers | (Yes) | (Yes) | ? | 37.0 (37.0) | (Yes) | ? | (Yes) | ? |
Indexed Database 2.0 | 58 | 58 | ? | ? | ? | ? | 45 | ? |
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.)