IDBCursor: delete() method

The delete() method of the IDBCursor interface returns an IDBRequest object, and, in a separate thread, deletes the record at the cursor's position, without changing the cursor's position. Once the record is deleted, the cursor's value is set to null.

Be aware that you can't call delete() (or IDBCursor.update()) on cursors obtained from IDBIndex.openKeyCursor(). For such needs, you have to use IDBIndex.openCursor() instead.

Note: This feature is available in Web Workers

Syntax

js

delete()

Parameters

None.

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 one of the following types:

TransactionInactiveError DOMException

Thrown if this IDBCursor's transaction is inactive.

ReadOnlyError DOMException

Thrown if the transaction mode is read-only.

InvalidStateError DOMException

Thrown if the cursor was created using IDBindex.openKeyCursor, is currently being iterated, or has iterated past its end.

Examples

In this simple fragment we create a transaction, retrieve an object store, then use a cursor to iterate through all the records in the object store. If the albumTitle of the current cursor is "Grace under pressure", we delete that entire record using const request = cursor.delete();.

The cursor does not require us to select the data based on a key; we can just grab all of it. Also note that in each iteration of the loop, you can grab data from the current record under the cursor object using cursor.value.foo. For a complete working example, see our IDBCursor example (View the example live).

js

function deleteResult() {
  list.textContent = "";
  const transaction = db.transaction(["rushAlbumList"], "readwrite");
  const objectStore = transaction.objectStore("rushAlbumList");

  objectStore.openCursor().onsuccess = (event) => {
    const cursor = event.target.result;
    if (cursor) {
      if (cursor.value.albumTitle === "Grace under pressure") {
        const request = cursor.delete();
        request.onsuccess = () => {
          console.log(
            "Deleted that mediocre album from 1984. Even Power windows is better."
          );
        };
      } else {
        const listItem = document.createElement("li");
        listItem.textContent = `${cursor.value.albumTitle}, ${cursor.value.year}`;
        list.appendChild(listItem);
      }
      cursor.continue();
    } else {
      console.log("Entries displayed.");
    }
  };
}

Specifications

Specification
Indexed Database API 3.0
# ref-for-dom-idbcursor-delete①

Browser compatibility

BCD tables only load in the browser

See also