docs: function runWrites (db, callback) {
    var tx, store;
  
    try {
      tx = db.transaction(['people', 'notes'], 'readwrite');
    } catch (err) {
      callback(err);
      return;
    }
  
    tx.onerror = function (err) {
      callback(err);
    };
  
    tx.oncomplete = function () {
      callback(null, null);
    };
  
    try {
      store = tx.objectStore('people');
      store.add({ name: 'Harry', created: (new Date()).toString() });
  
      store = tx.objectStore('notes');
      store.add({ note: 'blah', created: (new Date()).toString() });
    } catch (err) {
      callback(err);
    }
  }