Laravel - SQLSTATE[23000]：完整性约束违反: 1451

Question

你好，我的laravel 9应用程序出现了以下错误: SQLSTATE23000:完整性约束违反: 1451不能删除或更新父行:外键约束失败

delete from
  `users`
where
  `id` = 1

我的代码

  <tbody>
    @foreach ($users as $user)               
    <tr class="text-center">
        <th>#{{$user->id}}</th>
        <td>{{$user->code}}</td>
        <td>{{$user->role}}</td>
        <td>{{$user->name}}</td>
        <td>{{$user->email}}</td>
        <td>{{$user->created_at}}</td>
        <td>{{$user->updated_at}}</td>
        <td>{{$user->updated_at}}</td>
        <td class="d-flex justify-content-between">
          <a href="{{ route('admin.edit', $user->id) }}" class="btn btn-outline-warning text-center"><i class="fa-solid fa-user-pen ms-1"></i></a>
          <a href="" class="btn btn-outline-primary text-center"><i class="fa-solid fa-envelope"></i></a>

          <div>
            <button class="btn btn-outline-danger text-center userDelete"><i class="fa-solid fa-circle-xmark"></i></button>
          </div>

            <!-- The Modal -->
            <div id="confirmDelete" class="custom-confirm">
              <!-- Modal content -->
              <div class="modal-content text-center">
                  <p>Sei sicuro di voler <span class="text-danger">cancellare</span> l'utente?</p>
                  <form action="{{route('admin.destroy', $user->id)}}" method="POST">
                      @csrf
                      @method('DELETE')
                      <button type="submit" class="btn btn-success me-3">Conferma</button>
                      <span class="cancelDelete btn btn-warning">Annulla</span>
                  </form>
              </div>  
          </div> 
        </td>
    </tr>
    @endforeach
  </tbody>

在没有确认模式的情况下，它正在处理的只是：

   <form action="{{route('admin.destroy', $user->id)}}" method="POST">
     @csrf
     @method('DELETE')
     <button type="submit" class="btn btn-success me-3">Conferma</button>
     <span class="cancelDelete btn btn-warning">Annulla</span>
   </form>

我为什么要犯这个错误？

问题截图误差图像

Answer 1

table.You上有外键，需要从相关表中删除第一个相关行。例如，如果我们有posts和comment**s，我们需要从包含post_id的comments**表中删除。在代码中如下所示：

$post = Post::findOrFail($id);
$comments = Comment::where('post_id', $id)->delete();

$post->delete();