Eloquent 查询构建复杂查询以获取在同一 table 的 2 个不同列中搜索 ID 的唯一记录

Question

我正在将一个项目迁移到 Laravel 4，但我遇到了一个非常复杂的查询，我想将其迁移到适当的 Eloquent 查询中。

我有一个包含聊天消息的 table，名为 chat_messages，代表模型 Chatmessage

table 包含发件人和收件人列，用户 ID 链接到 users table 和 User 模型。

在旧版本的应用程序中获取包含原始 SQL 中所有聊天伙伴的所有用户 ID 的列表的查询如下：

$sql_allChatPartners = "SELECT DISTINCT chatPartner   
FROM ( SELECT * FROM (
    SELECT cm_receipient AS chatPartner, cm_sent_at
    FROM chat_messages WHERE cm_sender = '".$me->userID."'
    UNION
    SELECT cm_sender AS chatPartner, cm_sent_at
    FROM chat_messages WHERE cm_receipient = '".$me->userID."'
) whateva ORDER BY whateva.cm_sent_at DESC ) other";

很抱歉命名 "fake" tables whateva 和其他 :-)

谁能告诉我用 Eloquent Querybuilder 做这件事的正确方向？

重要的是我以正确的顺序获取 chatPartner ID 列表，其中最后一条聊天消息已作为第一个 chatPartner 交换。聊天中最长时间不活动的 chatPartner 作为最后一个条目。

这是我到目前为止在我的用户模型中得到的...

public function allopenchats(){
 $asSender = Chatmessage::where('sender', $this->id)->select('receipient as chatPartner, created_at');
 $asBoth = Chatmessage::where('receipient', $this->id)->select('sender as chatPartner, created_at')
              ->union($asSender)->orderBy('created_at', 'desc')->get();
}

为了新版本

非常感谢您的帮助！

Answer 1

您sql可能会更改为：

    SELECT IF (cm_receipient = '10', cm_sender, IF (cm_sender = '10',cm_receipient, 'no')) AS chatPartner, cm_sent_at
FROM chat_messages
WHERE cm_receipient = '10' OR cm_sender = '10'
GROUP BY chatPartner
HAVING chatPartner != 'no'

按 cm_sent_at DESC

排序

形式：

Chatmessage::where('sender','=',$this->id)
    ->orWhere('receipient','=',$this->id)
    ->select(DB::raw('IF (receipient = '.$this->id.', sender, IF (sender = '.$this->id.',receipient, 'no' )) AS chatPartner'), 'created_at')
    ->groupBy('chatPartner')
    ->having('chatPartner', '!=', 'no')
    ->orderBy('created_at', 'desc')
    ->get();

Answer 2

非常感谢Vitalik_74，没有他我不会走那么远。现在是最终查询，虽然它不在 ORM 中，但它工作正常并为我提供了我需要的结果。

$result = DB::select("SELECT * 
            FROM (
               SELECT IF( receipient =  '".$this->id."', sender, IF( sender =  '".$this->id."', receipient,  'no' ) ) AS chatPartner, created_at
               FROM chatmessages
               WHERE receipient =  '".$this->id."'
               OR sender =  '".$this->id."'
               HAVING chatPartner !=  'no'
               ORDER BY created_at DESC
            )whateva
            GROUP BY whateva.chatPartner
            ORDER BY whateva.created_at DESC");

如果有人可以使用 Laravel 查询生成器执行此查询，我将很高兴看到。现在我先这样吧。

Eloquent 查询构建复杂查询以获取在同一 table 的 2 个不同列中搜索 ID 的唯一记录

Eloquent query building complex query to get unique records searching for an ID in 2 different columns in same table

mysql

eloquent

laravel-4