laravel 按关系列排序
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Order by relationship column
提问by TheUnreal
I have the following query:
我有以下查询：
$items = UserItems::with('item')
->where('user_id','=',$this->id)
->where('quantity','>',0)
->get();
I need to order it by item.type so I tried:
我需要按 item.type 订购，所以我试过：
$items = UserItems::with('item')
->where('user_id','=',$this->id)
->where('quantity','>',0)
->orderBy('item.type')
->get();
but I get Unknown column 'item.type' in 'order clause'
但我明白了 Unknown column 'item.type' in 'order clause'
What I am missing?
我缺少什么？
回答by TheUnreal
join() worked fine thanks to @rypskarcomment
由于@rypskar评论，join() 工作正常
$items = UserItems
::where('user_id','=',$this->id)
->where('quantity','>',0)
->join('items', 'items.id', '=', 'user_items.item_id')
->orderBy('items.type')
->select('user_items.*') //see PS:
->get();
PS: To avoid the idattribute (or any shared name attribute between the two tables) to overlap and resulting in the wrong value, you should specify the select limit with select('user_items.*').
PS：为避免id属性（或两个表之间的任何共享名称属性）重叠并导致错误值，您应该使用select('user_items.*').
回答by Repox
Well, your eager loading is probably not building the query you're expecting, and you can check it by enabling the query log.
好吧，您的急切加载可能没有构建您期望的查询，您可以通过启用查询日志来检查它。
But I would probably just use a collection filter:
但我可能只会使用集合过滤器：
$items = UserItems::where('user_id','=',$this->id)
->where('quantity','>',0)
->get()
->sortBy(function($useritem, $key) {
return $useritem->item->type;
});
回答by Κουντρ?τ Σπ?ρου-Μαντ?λ
I found another way of sorting a dataset using a field from a related model, you can get a function in the model that gets a unique relation to the related table(ex: table room related to room category, and the room is related to a category by category id, you can have a function like 'room_category' which returns the related category based on the category id of the Room Model) and after that the code will be the following:
我找到了另一种使用相关模型中的字段对数据集进行排序的方法，您可以在模型中获得一个函数，该函数获得与相关表的唯一关系（例如：与房间类别相关的表房间，而房间与按类别 id 分类，你可以有一个像“room_category”这样的函数，它根据房间模型的类别 id 返回相关的类别），然后代码如下：
Room::with('room_category')->all()->sortBy('room_category.name',SORT_REGULAR,false);
This will get you the rooms sorted by category name
这将为您提供按类别名称排序的房间
I did this on a project where i had a DataTable with Server side processing and i had a case where it was required to sort by a field of a related entity, i did it like this and it works. More easier, more proper to MVC standards.
我在一个项目中做了这个，我有一个带有服务器端处理的 DataTable，我有一个案例，需要按相关实体的字段进行排序，我这样做了，并且可以正常工作。更容易，更适合 MVC 标准。
In your case it will be in a similar fashion:
在您的情况下，它将采用类似的方式：
User::with('item')->where('quantity','>',0)->get()->sortBy('item.type',SORT_REGULAR,false);
