Question

我使用两个表的内连接进行简单的选择查询。问题是，当我返回标题时，我才收到此错误：

尝试获取非对象的属性

但是当我返回所有的json时，它的效果非常好。我想用标题来查询。我该如何解决这个问题？

    $products = DB::table('products');
    $messages = $products
        ->join('bookings', 'products.id', '=', 'bookings.ProductID')
        ->where('EmailAddress', '=', ''. $userEmail . '')
        ->orderBy("bookings.DateCreated", "desc")
        ->get();
    return $messages->Title;

Answer 1

您的代码或查询返回多个Result，因此您需要循环或迭代它： -

$products = DB::table('products');
$messages = $products
    ->join('bookings', 'products.id', '=', 'bookings.ProductID')
    ->where('EmailAddress', '=', ''. $userEmail . '')
    ->orderBy("bookings.DateCreated", "desc")
    ->get();
return $messages->Title;

根据您的代码，您似乎只需要第一行结果，因此将代码更改为（replace - ＆gt; get（）with - ＆gt; first（））： -

$products = DB::table('products');
$messages = $products
    ->join('bookings', 'products.id', '=', 'bookings.ProductID')
    ->where('EmailAddress', '=', ''. $userEmail . '')
    ->orderBy("bookings.DateCreated", "desc")
    ->first();
return $messages->Title;

Answer 2

为什么不能尝试使用Eloquent Eager Loading。所以你将获得Object返回。

$messages = Products::with(['bookings' => function ($query) use ($userEmail) {
    $query->where('EmailAddress', '=', ''. $userEmail . '');
    $query->orderBy("bookings.DateCreated", "desc");
}])->get();

Try similar like this. Hope you will get the collection.

Answer 3

感谢答案。但我找到了解决方案。我曾经在内部加入并添加别名。

    $products = DB::table('products');
    $messages = $products
        ->join('bookings AS b1', 'products.id', '=', 'b1.ProductID')
        ->join('booking_notifications as b2', 'b1.Code', '=', 'b2.Code')
        ->where('Products.EmailAddress', '=', ''. $userEmail . '')
        ->orderBy("b1.DateCreated", "desc")       
        ->get(); 

    return view('messages.index')->with('messages', $messages);;

Laravel内部联接仅返回特定结果

3 个答案: