在即时表格中存储ID（找不到最新信息）

Question

我在帖子和标签

之间有很多关系

问题是，当我想获取帖子ID和标签ID以将其链接到他们的即时表中时，我做了一个简单的查询，然后在laravel查询中使用了 latest（）方法生成器，并引发此错误：

  

方法Illuminate \ Support \ Collection :: latest不存在。

这是我的商店功能：

  public function store(Request $request)
  {
    {
      $this->validate($request,[
        'title'=>'required',
        'body'=>'required',
        'tags'=>'required',
        'slug'=>'required',

      ]);

      $input = $request->all();
        $tags = explode(",", $request->tags);

          if ($input != null) {
            $post = post::create($input);
            $post->tag($tags);
            // the problem is in this two lines
            $post_id = DB::table('posts')->pluck('id')->latest();
            $tagged_id = DB::table('tagging_tagged')->pluck('id')->latest();
            //
            dd($tagged_id , $post_id);
            $relationship = new post_tagged;
            $relationship->post_id = $post_id;
            $relationship->tagged_id = $tagged_id;
            $relationship->save();
            return redirect('/admin/blog')->with('success' , 'Post added successfully');
          }
          return redirect('/admin/blog');
    }
 }

我想用这两行实现的想法是在发布表和标签表（这是最新发布）中获取最新的ID。 然后将其存储在即时表中

我这样做是为了解决问题

存储功能

  public function store(Request $request)
  {
    {
      $this->validate($request,[
        'title'=>'required',
        'body'=>'required',
        'tags'=>'required',
        'slug'=>'required',

      ]);

      $input = $request->all();
        $tags = explode(",", $request->tags);

          if ($input != null) {
            $post = post::create($input);
            $post->tag($tags);
            $post_id = DB::table('tagging_tagged')->latest('taggable_id')->first();
            $post_id = $post_id->taggable_id;
            $tagged_id = DB::table('tagging_tagged')->latest('id')->first();
            $tagged_id = $tagged_id->id;
            $relationship = new post_tagged;
            $relationship->post_id = $post_id;
            $relationship->tagged_id = $tagged_id;
            $relationship->save();
            return redirect('/admin/blog')->with('success' , 'Post added successfully');
          }
          return redirect('/admin/blog');
         }