选择列总和等于Laravel中另一个表上另一列的值的所有行

Question

Select all rows where the sum of column equals a value of another column on another table in Laravel

purchases

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

payments

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

Code

$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();

When I run the code I get the following error Column not found: 1054 Unknown column 'amount' in 'having clause'

Expected Result

id | name               | total
1  | Gamerzone Book       40

I tried with all these but nothing seems to be working

$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 will work as a subquery to get total for each purchase line.

As a result we get sql like :

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