```js
// Tests only against the local state
if (post.title.startsWith('[Amplify]')) {
  await DataStore.save(
    Post.copyOf(post, (updated) => {
      updated.title = 'Updated Title';
    })
  );
}

// Only applies the update if the data in the remote backend satisfies the criteria
await DataStore.save(
  Post.copyOf(post, (updated) => {
    updated.title = 'Updated title';
  }),
  (p) => p.title.beginsWith('[Amplify]')
);
```