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IDBIndex: keyPath property

The keyPath property of the IDBIndex interface returns the key path of the current index. If null, this index is not auto-populated.

Note: This feature is available in Web Workers

Value

Any data type that can be used as a key path.

Examples

In the following example we open a transaction and an object store, then get the index lName from a simple contacts database. We then open a basic cursor on the index using IDBIndex.openCursor — this works the same as opening a cursor directly on an ObjectStore using IDBObjectStore.openCursor except that the returned records are sorted based on the index, not the primary key.

The key path of the current index is logged to the console: it should be returned as lName.

Finally, we iterate through each record, and insert the data into an HTML table. For a complete working example, see our IndexedDB-examples demo repo (View the example live).

js

function displayDataByIndex() {
  tableEntry.innerHTML = "";
  const transaction = db.transaction(["contactsList"], "readonly");
  const objectStore = transaction.objectStore("contactsList");

  const myIndex = objectStore.index("lName");
  console.log(myIndex.keyPath);

  myIndex.openCursor().onsuccess = (event) => {
    const cursor = event.target.result;
    if (cursor) {
      const tableRow = document.createElement("tr");
      tableRow.innerHTML =
        `<td>${cursor.value.id}</td>` +
        `<td>${cursor.value.lName}</td>` +
        `<td>${cursor.value.fName}</td>` +
        `<td>${cursor.value.jTitle}</td>` +
        `<td>${cursor.value.company}</td>` +
        `<td>${cursor.value.eMail}</td>` +
        `<td>${cursor.value.phone}</td>` +
        `<td>${cursor.value.age}</td>`;
      tableEntry.appendChild(tableRow);

      cursor.continue();
    } else {
      console.log("Entries all displayed.");
    }
  };
}

Specifications

Browser compatibility

Desktop Mobile
Chrome Edge Firefox Internet Explorer Opera Safari WebView Android Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet
keyPath 23 12 10 10 15 8 4.4 25 22 14 8 1.5

See also

© 2005–2023 MDN contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/IDBIndex/keyPath