orderBy 不能在 laravel + 数据表中工作

Question

我只想获取每个客户 ID 的最新日期/时间，但 orderBy 代码似乎不起作用。我已经尝试过使用，但我不断收到数据表错误 7。

控制器

public function refresh(){
    $cash_advance = DB::table('cash_advance')
        ->join('customer', 'customer.id', '=', 'cash_advance.customer_id')
        ->select('cash_advance.customer_id', 'customer.fname', 'customer.mname', 'customer.lname', 'cash_advance.amount', 'cash_advance.created_at', 'cash_advance.balance')
        ->groupBy('cash_advance.customer_id')
        ->orderBy('cash_advance.created_at', 'desc')
        ->get();
    return \DataTables::of($cash_advance)
    ->addColumn('action', function($cash_advance){
        return '<button class="btn btn-xs btn-info" id="'.$cash_advance->customer_id.'"><i class="material-icons" style="width: 25px;">visibility</i></button>';//info/visibility
    })
    ->make(true);
}

数据表

var cash_advancetable = $('#cash_advancetable').DataTable({
            dom: 'Bfrtip',
            buttons: [
            ],
            processing: true,
            serverSide: true,
            ajax: "{{ route('refresh_cashadvance') }}",
            columns: [
                {render: function(data, type, full, meta){
                    return full.fname +" "+full.mname+" "+full.lname;
                }},
                {data: 'amount', name: 'amount'},
                {data: 'created_at', name: 'created_at'},
                {data: 'balance', name: 'balance'},
                {data: "action", orderable:false,searchable:false}
            ]
        });

output database

Answer 1

要获取最新日期，只需使用 max aggregator: max('cash_advance.created_at')。

但无论如何在上面的 groupBy 语句中，您应该选择所有与客户相关的功能 像这样：

    DB::table('cash_advance')
    ->join('customer', 'customer.id', '=', 'cash_advance.customer_id')
    ->select('cash_advance.customer_id', 'customer.fname', 'customer.mname', 'customer.lname', 'cash_advance.amount', 'cash_advance.balance', DB::raw('MAX( cash_advance.created_at)'))
    ->groupBy('cash_advance.customer_id', 'customer.fname', 'customer.mname', 'customer.lname', 'cash_advance.amount', 'cash_advance.balance',)
    ->orderBy('cash_advance.customer_id', 'customer.fname', 'customer.mname', 'customer.lname', 'cash_advance.amount', 'cash_advance.balance', 'desc')
    ->get();