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  <title>IndexedDB — get modify put</title>
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    body {
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    p { margin: 0 0 1rem; max-width: 440px; }
    label { display: block; margin-bottom: 0.35rem; font-size: 0.875rem; font-weight: 600; }
    input {
      display: block;
      width: 100%;
      max-width: 300px;
      padding: 0.5rem 0.65rem;
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    }
    #status.ok { border-left: 4px solid #22c55e; }
    #status.err { border-left: 4px solid #ef4444; }
  </style>
</head>
<body>
  <h1>Read–modify–write</h1>
  <p>Load id 1 with <code>get()</code>, change the title field, then <code>put()</code> the whole object back.</p>

  <label for="title">New title</label>
  <input type="text" id="title" value="Revised draft">

  <button type="button" id="saveBtn" disabled>Update note id 1</button>
  <p id="status">Opening database&hellip;</p>

  <script>
    var statusEl = document.getElementById('status');
    var db;

    var openReq = indexedDB.open('tryitGetPutDemo', 1);

    openReq.onupgradeneeded = function (event) {
      var store = event.target.result.createObjectStore('notes', { keyPath: 'id' });
      store.transaction.objectStore('notes').put({
        id: 1,
        title: 'Original draft',
        body: 'Keep this body text unchanged.'
      });
    };

    openReq.onsuccess = function (event) {
      db = event.target.result;
      statusEl.textContent = 'Note id 1 is seeded. Enter a new title and click Update.';
      statusEl.className = 'ok';
      document.getElementById('saveBtn').disabled = false;
    };

    document.getElementById('saveBtn').addEventListener('click', function () {
      var newTitle = document.getElementById('title').value.trim();
      if (!newTitle) {
        statusEl.textContent = 'Please enter a title.';
        statusEl.className = 'err';
        return;
      }

      var tx = db.transaction(['notes'], 'readwrite');
      var store = tx.objectStore('notes');
      var getReq = store.get(1);

      getReq.onsuccess = function () {
        var record = getReq.result;
        if (!record) {
          statusEl.textContent = 'Record id 1 not found.';
          statusEl.className = 'err';
          return;
        }

        record.title = newTitle;
        record.updatedAt = new Date().toISOString();

        var putReq = store.put(record);
        putReq.onsuccess = function () {
          statusEl.textContent = 'Updated title to "' + newTitle + '". Body field preserved.';
          statusEl.className = 'ok';
        };
      };

      getReq.onerror = function (event) {
        statusEl.textContent = 'Get failed: ' + event.target.error.message;
        statusEl.className = 'err';
      };
    });
  </script>
</body>
</html>
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IndexedDB UPDATE — get(), Modify, put()
