【Laravel / クエリビルダ】DB::rawの使い方が正しくない

Question

初学者です。
お力添えいただけると幸いです。

やりたいこと

特定のテーブルから2つのカラム情報を配列で取得して、さらに追加でカラム（item）を作成し、文字列（出金）を出力したいです。

設計

+------------+-----------------+------+-----+---------+----------------+
| Field      | Type            | Null | Key | Default | Extra          |
+------------+-----------------+------+-----+---------+----------------+
| id         | bigint unsigned | NO   | PRI | NULL    | auto_increment |
| user_id    | int unsigned    | NO   |     | NULL    |                |
| bank_type  | int unsigned    | NO   |     | NULL    |                |
| bank_id    | int unsigned    | NO   |     | NULL    |                |
| amount     | varchar(100)    | NO   |     | NULL    |                |
| verified   | date            | YES  |     | NULL    |                |
| created_at | timestamp       | YES  |     | NULL    |                |
| updated_at | timestamp       | YES  |     | NULL    |                |
| deleted_at | timestamp       | YES  |     | NULL    |                |
+------------+-----------------+------+-----+---------+----------------+

該当コード

$details = DB::table('withdrawals')
    ->select([
        'withdrawals.amount AS amount',
        'withdrawals.created_at AS created_at',
        DB::raw("substr('出金') AS item"),
    ])
    ->where('withdrawals.user_id', '=', 1)
    ->orderBy('created_at', 'desc')
    ->get();
dd($details);

エラーメッセージ

SQLSTATE[42000]: Syntax error or access violation: 1064 You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ') AS item from `withdrawals` where `withdrawals`.`user_id` = ? order by `created' at line 1 (SQL: select `withdrawals`.`amount` as `amount`, `withdrawals`.`created_at` as `created_at`, substr('出金') AS item from `withdrawals` where `withdrawals`.`user_id` = 1 order by `created_at` desc)

DB::rawをコメントアウトすると、以下のように取得できるので、エラーの原因はDB::rawということがわかっているのですが、原因がわからず、、、

Illuminate\Support\Collection {#1548 ▼
  #items: array:1 [▼
    0 => {#1547 ▼
      +"amount": "30000"
      +"created_at": "2021-02-02 19:30:28"
    }
  ]
}

お力添えいただけると幸いです。

Answer 1

申し訳ございません、以下で大丈夫でした、、、

$details = DB::table('withdrawals')
    ->select([
        'withdrawals.amount AS amount',
        'withdrawals.created_at AS created_at',
        DB::raw("'商品' AS item"),
    ])
    ->where('withdrawals.user_id', '=', 1)
    ->orderBy('created_at', 'desc')
    ->get();
dd($details);