IDBObjectStore.add()
The add()
method of the IDBObjectStore
interface returns an IDBRequest
object, and, in a separate thread, creates a structured clone of the value, and stores the cloned value in the object store. This is for adding new records to an object store.
To determine if the add operation has completed successfully, listen for the
transaction's complete
event in addition to the
IDBObjectStore.add
request's success
event, because the
transaction may still fail after the success event fires. In other words, the success
event is only triggered when the transaction has been successfully queued.
The add method is an insert only method. If a
record already exists in the object store with the key
parameter as its
key, then an error ConstrainError
event is fired on the returned request
object. For updating existing records, you should use the
IDBObjectStore.put
method instead.
Note: This feature is available in Web Workers
Syntax
var request = objectStore.add(value);
var request = objectStore.add(value, key);
Parameters
- value
-
The value to be stored.
- key Optional
-
The key to use to identify the record. If unspecified, it results to null.
Returns
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:
ReadOnlyError
DOMException
-
Thrown if the transaction associated with this operation is in read-only mode.
TransactionInactiveError
DOMException
-
Thrown if this
IDBObjectStore
's transaction is inactive. DataError
DOMException
-
Thrown if any of the following conditions apply:
- The object store uses in-line keys or has a key generator, and a key parameter was provided.
- The object store uses out-of-line keys and has no key generator, and no key parameter was provided.
- The object store uses in-line keys but no key generator, and the object store's key path does not yield a valid key.
- The key parameter was provided but does not contain a valid key.
InvalidStateError
DOMException
-
Thrown if the
IDBObjectStore
has been deleted or removed. DataCloneError
DOMException
-
Thrown if the data being stored could not be cloned by the internal structured cloning algorithm.
ConstraintError
DOMException
-
Thrown if an insert operation failed because the primary key constraint was violated (due to an already existing record with the same primary key value).
Example
In the following code snippet, we open a read/write transaction on our database and add
some data to an object store using add()
. Note also the functions attached
to transaction event handlers to report on the outcome of the transaction opening in the
event of success or failure. 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 initialized.</li>';
// store the result of opening the database in the db variable.
// This is used a lot below
db = DBOpenRequest.result;
// Run the addData() function to add the data to the database
addData();
};
function addData() {
// Create a new object ready to insert into the IDB
var newItem = [ { taskTitle: "Walk dog", hours: 19, minutes: 30, day: 24, month: "December", year: 2013, notified: "no" } ];
// open a read/write db transaction, ready for adding 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. Duplicate items not allowed.</li>';
};
// create an object store on the transaction
var objectStore = transaction.objectStore("toDoList");
// Make a request to add our newItem object to the object store
var objectStoreRequest = objectStore.add(newItem[0]);
objectStoreRequest.onsuccess = function(event) {
// report the success of our request
note.innerHTML += '<li>Request successful.</li>';
};
};
Specifications
Specification |
---|
Indexed Database API 3.0 # ref-for-dom-idbobjectstore-add① |
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.)