Laravel Eloquent - 获取相关模型的最后插入
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Laravel Eloquent - get last insert of related model
提问by Scarwolf
I have a relationship between two models: Terminaland terminalRent.
我有两个模型之间的关系：Terminal和terminalRent。
A Terminal can have many terminalRents. I want to get the last Rent for a specific Terminal.
一个终端可以有多个终端租金。我想获得特定终端的最后租金。
$lastRent = Terminal::with('terminalRent')->where('id', $id)->orderBy('id', 'desc')->first();
When using where()it will reflect those on the Modalhoewever I want to get the last record for terminalRent in relation to the specific terminal. $idis the Id of the terminal and the tables are connected like this:
使用where()时它将反映那些Modal我想获得与特定终端相关的 terminalRent 的最后一条记录。$id是终端的 ID，表格的连接方式如下：
Terminal
----
ID
terminalRent
-----
ID
terminal_id <--- this is the foreign key for the ID of the Terminal Table
回答by ExohJosh
If the relationship between Terminal and Terminal rent is hasMany you can do something like:
如果终端和终端租金之间的关系是 hasMany 你可以这样做：
$lastRented = $lastRent->terminalRent->last();
Ensure you have the last rented via dd($lastRented);
确保您有最后一次租借通过 dd($lastRented);
Let me know how you get on
让我知道你是怎么办的
Edit: If this gives you the incorrect instance of terminalRent try first(); I can't remember how Eloquent orders eagerlaoded relationships by default.
编辑：如果这给你错误的 terminalRent 实例，请尝试 first(); 我不记得默认情况下 Eloquent 是如何命令急切的关系的。
回答by Parithiban
Try This Code
试试这个代码
$lastRent = Terminal::with(['terminalRent' => function ($query) {
$query->orderBy('id', 'desc')->first();
}]);
回答by Ivanka Todorova
You can join them and then order the results based on terminalRent.idand pick the first one:
您可以加入它们，然后根据结果排序terminalRent.id并选择第一个：
$lastRent = Terminal::join('terminalRent', 'terminalRent.terminal_id','=','Terminal.id')->where('Terminal.id', $id)->orderBy('terminalRent.id', 'desc')->first();
回答by Adrenaxus
Use this to get the last rent for a specific Terminal:
使用它来获取特定终端的最后租金：
$terminal = Terminal::find($id); //the terminal for which you want to get the last rent
$lastRent = $terminal->rentals()->orderBy('id', 'DESC')->first();
Keep in mind that this is only one way to do it, there might be other options that suit your needs better.
请记住，这只是一种方法，可能还有其他更适合您需求的选择。
