IDBObjectStore: delete() method
The delete()
method of the
IDBObjectStore
interface returns an IDBRequest
object,
and, in a separate thread, deletes the specified record or records.
Either a key or an IDBKeyRange
can be passed, allowing one or multiple
records to be deleted from a store. To delete all records in a store, use
IDBObjectStore.clear
.
Bear in mind that if you are using a IDBCursor
, you can use
the IDBCursor.delete()
method to more efficiently delete the current
record — without having to explicitly look up the record's key.
Note: This feature is available in Web Workers
Syntax
js
delete(key)
Parameters
key
-
The key of the record to be deleted, or an
IDBKeyRange
to delete all records with keys in range.
Return value
An IDBRequest
object on which subsequent events related to this operation are fired.
If the operation is successful, the value of the request's result
property is undefined
.
Exceptions
This method may raise a DOMException
of the following types:
TransactionInactiveError
DOMException
-
Thrown if this object store's transaction is inactive.
ReadOnlyError
DOMException
-
Thrown if the object store's transaction mode is read-only.
InvalidStateError
DOMException
-
Thrown if the object store has been deleted.
DataError
DOMException
Examples
The following code snippet shows the deleteItem()
function,
which is part of the To-do Notifications example app. This app stores to-do
list items using IndexedDB. You can
see the app's complete code on GitHub, and
try out the app live.
The deleteItem()
function is called when the user clicks the
button to delete a to-do list item. The item key is set in the button's
'data-task'
data attribute, so the function
knows which item to delete. The function opens a database transaction in
which to delete the item, supplying its key. When the transaction completes,
the function updates the app UI to report that the item was deleted.
Note that in this function db
is a global variable
referring to an IDBDatabase
object that is initialized when
the app loads.
js
function deleteItem(event) {
// retrieve the name of the task we want to delete
let dataTask = event.target.getAttribute("data-task");
// open a database transaction and delete the task, finding it by the name we retrieved above
let transaction = db.transaction(["toDoList"], "readwrite");
let request = transaction.objectStore("toDoList").delete(dataTask);
// report that the data item has been deleted
transaction.oncomplete = () => {
// delete the parent of the button, which is the list item, so it no longer is displayed
event.target.parentNode.parentNode.removeChild(event.target.parentNode);
note.innerHTML += `<li>Task "${dataTask}" deleted.</li>`;
};
}
Specifications
Specification |
---|
Indexed Database API 3.0 # ref-for-dom-idbobjectstore-delete① |
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 the example live).