選擇列總和等於Laravel中另一個表上另一列的值的所有行

Question

選擇列總和等於Laravel中另一個表上另一列的值的所有行

購買

id | name               | amount
1  | Gamerzone Book     | 40
2  | Recipe Book        | 20
3  | EngineX Book       | 10

付款方式

id  | purchase_id  | amount  
1     1              25       
2     1              15       
2     2              10   

碼

$query = DB::table('purchases')
        ->select(['purchases.id','purchases.name',
                   DB::raw("IFNULL(sum(payments.amount),0) as total")
            ])
         ->leftJoin('payments','payments.purchase_id','=','purchases.id')
         ->having('amount','=',DB::raw('total'));
         ->groupBy('purchases.id')->get();

當我運行代碼時，出現以下錯誤找不到列：1054“具有子句”中的未知列“金額”

預期結果

id | name               | total
1  | Gamerzone Book       40

我嘗試了所有這些，但似乎沒有任何效果

$query->where('purchases.amount','=',DB::raw('total'));
$query->having(DB::raw('purchases.amount'),'=',DB::raw('total'));
$query->havingRaw('IFNULL(sum(purchases.amount),0) = purchases.amount');

Answer 1

$paymentsQuery = DB::table('payments')->select(DB::raw("IFNULL(sum(payments.amount),0) as total"))->whereRaw('purchases.id = purchase_id')->groupBy('purchase_id');

$purchasesQuery = DB::table('purchases')->select(['id', 'name', 'amount', DB::raw('(' . $paymentsQuery->toSql() . ') as total')])->havingRaw('amount = total')->mergeBindings($paymentsQuery);

$result = $purchasesQuery->get();

$ paymentsQuery將作為子查詢來獲取每個購買行的總計。

結果我們得到像這樣的sql：

select `id`, `name`, `amount`, 
(select IFNULL(sum(payments.amount),0) as total from `payments` where purchases.id = purchase_id group by `purchase_id`) as total 
from `purchases` 
having amount = total