Laravel日期比较不适用于列中创建的\u

Question

我写了一个查询，用于检查在对话中的用户删除写入对话的消息后。下面是我的问题：

$messages = DB::table('conversations')
                    ->where('conversations.id', $conversation->id)
                    ->join('messages', 'messages.conversation_id', '=', 'conversations.id')
                    ->join('deleted_conversations', 'deleted_conversations.conversation_id', '=', 'conversations.id')
                    ->where('messages.created_at', '>=', 'deleted_conversations.created_at')
                    ->orderBy('messages.created_at', 'desc')
                    ->select('messages.*')
                    ->get()
                    ->all();

但是每次我尝试使用where（'messages.created\u at，'

以下是迁移：

Schema::create('conversations', function (Blueprint $table) {
            $table->id();
            $table->integer('sender_id');
            $table->integer('receiver_id');
            $table->enum('status', ['read', 'unread']);
            $table->timestamps();
        });

 Schema::create('messages', function (Blueprint $table) {
            $table->id();
            $table->integer('conversation_id');
            $table->integer('sender_id');
            $table->string('message');
            $table->timestamps();
        });

Schema::create('deleted_conversations', function (Blueprint $table) {
            $table->id();
            $table->integer('conversation_id');
            $table->integer('user_id');
            $table->timestamps();
        });

已删除的会话表

对话表

消息表




Answer 1

当您想添加一个where子句，其中的值是另一列时，您需要使用WHOCOLUNT（）：

->whereColumn('messages.created_at', '>=', 'deleted_conversations.created_at')