php - 通过 ID 和所有外国人在 Laravel 5 中递归获取记录

Question

我有两个表，看起来(迁移):

Schema::create('sets', function(Blueprint $table)
{
    $table->increments('id');

    $table->string('key');

    $table->string('name');

    $table->string('set_type');

    $table->integer('belongs_to')->unsigned();

    $table->timestamps();

    $table->foreign('belongs_to')->references('id')->on('sets')->onDelete('cascade');

});

Schema::create('posts', function(Blueprint $table)
{
    $table->bigIncrements('id');

    $table->bigInteger('user_id')->unsigned();

    $table->bigInteger('set_id')->unsigned();

    $table->string('post_type', 25);

    $table->text('post');

    $table->boolean('is_reported')->default(false);

    $table->boolean('is_hidden')->default(false);

    $table->timestamps();

    $table->foreign('user_id')->references('id')->on('users');
    $table->foreign('set_id')->references('id')->on('sets');

});

“set”表用于存储应在其中查看帖子的位置(国家、城市...)的数据。例如，让我们存储一些国家:

   id | key               | name        | belongs_to
   1  | europe            | Europe      | null
   2  | germany-all       | Germany     | 1
   3  | germany-berlin    | Berlin      | 2
   4  | germany-frankfurt | Frankfurt   | 2
   5  | poland-all        | Poland      | 1
   6  | poland-warsaw     | Warsaw      | 5
   7  | england-all       | England     | 1

并且，我的帖子 set_id 为 6。从逻辑上看，当我想从欧洲(ID 1)获取帖子时，该帖子也应该返回，因为 6 属于 5，而 5 属于 1。这就是我想做的事。不使用太多 PHP 是可能的吗？

Answer 1

好的，我找到了最佳解决方案。这是嵌套集模式。我用了baum包，看起来:

对于 sets 表，我添加了 Baum 的列:

Schema::create('sets', function(Blueprint $table) {
   $table->bigIncrements('id');
   $table->integer('parent_id')->nullable()->index();
   $table->integer('lft')->nullable()->index();
   $table->integer('rgt')->nullable()->index();
   $table->integer('depth')->nullable();

   $table->string('key');
   $table->string('name');
   $table->string('set_type');

   $table->timestamps();
});

完成了!只需获取 set_id 并返回帖子，例如:

$sets = Set::where('key', '=', $myKey)->first()->getDescendantsAndSelf()->lists('id');
$posts = Post::whereIn('set_id', $sets)->with(['user'])->take(6)->get();

我将把它留给后代；)