IDBCursor: source property
Note: This feature is available in Web Workers.
  The source read-only property of the
  IDBCursor interface returns the IDBObjectStore or
  IDBIndex that the cursor is iterating over. This function never returns
  null or throws an exception, even if the cursor is currently being iterated, has
  iterated past its end, or its transaction is not active.
Value
  The IDBObjectStore or IDBIndex that the cursor is
  iterating over.
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. Within each iteration we
  log the source of the cursor, which will log our IDBObjectStore object to
  the console.
  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).
function displayData() {
  const transaction = db.transaction(["rushAlbumList"], "readonly");
  const objectStore = transaction.objectStore("rushAlbumList");
  objectStore.openCursor().onsuccess = (event) => {
    const cursor = event.target.result;
    if (cursor) {
      const listItem = document.createElement("li");
      listItem.textContent = `${cursor.value.albumTitle}, ${cursor.value.year}`;
      list.appendChild(listItem);
      console.log(cursor.source);
      cursor.continue();
    } else {
      console.log("Entries all displayed.");
    }
  };
}
Specifications
| Specification | 
|---|
| Indexed Database API 3.0  # ref-for-dom-idbcursor-source①  | 
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).