Laravel 查詢構建器選擇帶有原始查詢的數組

Question

我有一個查詢，涉及選擇多列的最新日期/值。 我用過mysql greatest功能。 我的問題是如何在已經有 select 語句的查詢構建器中使用或插入它。

這是我試過的查詢

$ses = DB::table('ses_contracts')
    ->join('ses_worker','ses_contracts.id','ses_worker.ses_id')
    ->join('corporates','corporates.id','ses_contracts.outsourcer')
    ->select([
        'corporates.corpname as outsourcer',
        'ses_contracts.outsourcer_manager_name as manager_name',
        'ses_worker.worker_name as worker_name',
        'ses_worker.sesnum1 as sesnum1',
        'ses_worker.sesnum2 as sesnum2',
        'ses_contracts.work_date1 as start',

        // this is the one i want the max_date for the 6 columns.
        DB::raw('SELECT GREATEST (work_date1,work_date2,work_date3,work_date4,work_date5,work_date6) as end from ses_contracts') 
       // end
    ])
    ->get();

die($ses);

部分結果是這個

{
    "outsourcer": "㈱daOn",
    "manager_name": "黃",
    "worker_name": "4",
    "sesnum1": "MS-JAN-",
    "sesnum2": 1,
    "start": "2021-10-29"
}

我想要的是

{
    "outsourcer": "㈱daOn",
    "manager_name": "黃",
    "worker_name": "4",
    "sesnum1": "MS-JAN-",
    "sesnum2": 1,
    "start": "2021-10-29",
    "end": "2021-10-30" // supposed oct 30 is latest date of the 6 columns
}

當我在 mysql 或DB::select語句中嘗試查詢時。 有用。 我只是不知道如何將它添加到現有的選擇中。 希望有人能幫忙。 謝謝你們。

Answer 1

使用selectRaw 。

$ses = DB::table('ses_contracts')
    ->join('ses_worker', 'ses_contracts.id', 'ses_worker.ses_id')
    ->join('corporates', 'corporates.id', 'ses_contracts.outsourcer')
    ->select([
        'corporates.corpname as outsourcer',
        'ses_contracts.outsourcer_manager_name as manager_name',
        'ses_worker.worker_name as worker_name',
        'ses_worker.sesnum1 as sesnum1',
        'ses_worker.sesnum2 as sesnum2',
        'ses_contracts.work_date1 as start'
    ])
    ->selectRaw('GREATEST(ses_contracts.work_date1, ses_contracts.work_date2, ses_contracts.work_date3, ses_contracts.work_date4, ses_contracts.work_date5, ses_contracts.work_date6) as end')
    ->get();

https://laravel.com/docs/8.x/queries#raw-methods