How to update a one-to-one relationship in Laravel?

Route::get('/users/update', method () {
    $user = User::with('posts')->find(1);
    $post = $user->posts()->whereId(1)->first();
    $post->title = 'Post title 1 updated';
    $post->push();
    return response()->json($user);
});

We open the browser and go to the new URL http://127.0.0.1:8000/users/update to find that the post has been updated successfully.

{
  "id": 1,
  "username": "John Doe",
  "created_at": "2023-09-06T17:24:02.000000Z",
  "updated_at": "2023-09-06T17:25:58.000000Z",
  "posts": [
    {
      "id": 1,
      "title": "Post title 1 updated",
      "body": "Post body 1",
      "user_id": 1,
      "created_at": "2023-09-06T17:28:58.000000Z",
      "updated_at": "2023-09-06T18:37:30.000000Z"
    },
    {
      "id": 5,
      "title": "Post title 5",
      "body": "Post body 5",
      "user_id": 1,
      "created_at": "2023-09-06T17:29:49.000000Z",
      "updated_at": "2023-09-06T17:29:49.000000Z"
    },
    {
      "id": 6,
      "title": "Post title 6",
      "body": "Post body 6",
      "user_id": 1,
      "created_at": "2023-09-06T17:29:49.000000Z",
      "updated_at": "2023-09-06T17:29:49.000000Z"
    }
  ]
}

Using update method.

First go to the file routes/web.php and modify this route.

Route::get('/users/update', method () {
    $user = User::with('posts')->find(1);
    $post = $user->posts()->whereId(1)->first();
    $post->title = 'Post title 1';
    $post->update();
    return response()->json($user);
]);

We open the browser and go to the new URL http://127.0.0.1:8000/users/update to find that the post has been updated successfully.

{
  "id": 1,
  "username": "John Doe",
  "created_at": "2023-09-06T17:24:02.000000Z",
  "updated_at": "2023-09-06T17:25:58.000000Z",
  "posts": [
    {
      "id": 1,
      "title": "Post title 1",
      "body": "Post body 1",
      "user_id": 1,
      "created_at": "2023-09-06T17:28:58.000000Z",
      "updated_at": "2023-09-06T18:41:35.000000Z"
    },
    {
      "id": 5,
      "title": "Post title 5",
      "body": "Post body 5",
      "user_id": 1,
      "created_at": "2023-09-06T17:29:49.000000Z",
      "updated_at": "2023-09-06T17:29:49.000000Z"
    },
    {
      "id": 6,
      "title": "Post title 6",
      "body": "Post body 6",
      "user_id": 1,
      "created_at": "2023-09-06T17:29:49.000000Z",
      "updated_at": "2023-09-06T17:29:49.000000Z"
    }
  ]
}

Update data using the post form. #

Using push method.

First go to routes/web.php file and add this route:

Route::get('/posts/update', method () {
    $post = Post::with('user')->find(1);
    $post->title = 'Post title 1 updated';
    $post->user->username = 'John Doe Updated';
    $post->push();
    return response()->json($post);
});

We open the browser and go to the new URL http://127.0.0.1:8000/posts/update to find that the post has been updated successfully.

{
  "id": 1,
  "title": "Post title 1 updated",
  "body": "Post body 1",
  "user_id": 1,
  "created_at": "2023-09-06T17:28:58.000000Z",
  "updated_at": "2023-09-06T18:50:30.000000Z",
  "user": {
    "id": 1,
    "username": "John Doe Updated",
    "created_at": "2023-09-06T17:24:02.000000Z",
    "updated_at": "2023-09-06T18:49:54.000000Z"
  }
}

Using update method.

First go to the file routes/web.php and modify this route.

Route::get('/posts/update', method () {
    $post = Post::with('user')->find(1);
    $post->user->username = 'John Doe';
    $post->update([
        'title' => 'Post title 1'
    ]);
    return response()->json($post);
]);

We open the browser and go to the new URL http://127.0.0.1:8000/posts/update to find that the post has been updated successfully.

{
  "id": 1,
  "title": "Post title 1",
  "body": "Post body 1",
  "user_id": 1,
  "created_at": "2023-09-06T17:28:58.000000Z",
  "updated_at": "2023-09-06T18:55:45.000000Z",
  "user": {
    "id": 1,
    "username": "John Doe",
    "created_at": "2023-09-06T17:24:02.000000Z",
    "updated_at": "2023-09-06T18:49:54.000000Z"
  }
}