IDBIndex: keyPath property

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.

Note: This feature is available in Web Workers.

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

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.textContent = "";
  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");
      for (const cell of [
        cursor.value.id,
        cursor.value.lName,
        cursor.value.fName,
        cursor.value.jTitle,
        cursor.value.company,
        cursor.value.eMail,
        cursor.value.phone,
        cursor.value.age,
      ]) {
        const tableCell = document.createElement("td");
        tableCell.textContent = cell;
        tableRow.appendChild(tableCell);
      }
      tableEntry.appendChild(tableRow);

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

Specifications

Specification
Indexed Database API 3.0
# dom-idbindex-keypath

Browser compatibility

desktop mobile
Chrome
Edge
Firefox
Opera
Safari
Chrome Android
Firefox for Android
Opera Android
Safari on iOS
Samsung Internet
WebView Android
WebView on iOS
keyPath
Chrome – Full support
Chrome 23 (Release date: 2012-11-06)
footnote Full support
Edge – Full support
Edge 12 (Release date: 2015-07-29)
footnote Full support
Firefox – Full support
Firefox 10 (Release date: 2012-01-31)
footnote Full support
Opera – Full support
Opera 15 (Release date: 2013-07-02)
footnote Full support
Safari – Full support
Safari 8 (Release date: 2014-10-16)
footnote Full support
Chrome Android – Full support
Chrome Android 25 (Release date: 2013-02-27)
footnote Full support
Firefox for Android – Full support
Firefox for Android 22 (Release date: 2013-06-25)
footnote Full support
Opera Android – Full support
Opera Android 14 (Release date: 2013-05-21)
footnote Full support
Safari on iOS – Full support
Safari on iOS 8 (Release date: 2014-09-17)
footnote Full support
Samsung Internet – Full support
Samsung Internet 1.5 (Release date: 2013-09-25)
footnote Full support
WebView Android – Full support
WebView Android 4.4 (Release date: 2013-12-09)
footnote Full support
WebView on iOS – Full support
WebView on iOS 8 (Release date: 2014-09-17)
footnote Full support

Legend

Tip: you can click/tap on a cell for more information.

Full support
Full support

See also