SQL Server 2019

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Create Table Payment (PaymentId Int, PaymentType VarChar(20), BillingId Int, PaymentAmount Money)
Create Table Billing (BillingId Int)
Insert Into Payment (PaymentId, PaymentType,  BillingId, PaymentAmount)
Values (12,      'electronic',    12345,      62.29),
(14,      'electronic',    12345,      73.28),
(56,      'electronic',    12345,     -62.29),
(6,       'electronic',    67890,      83.58),
(2,       'adjustment',    67890,      30.43)
5 rows affected

Insert Into Billing (BillingId)
Values (12345), (67890)
2 rows affected

Select B.BillingId, Sum(Case When P.PaymentType='electronic' Then P.PaymentAmount End) As [AmountPaid (electronic)],
					Sum(Case When P.PaymentType='adjustment' Then P.PaymentAmount End) As [AmountAdjusted (adjustment)] 
From Billing As B Left Join Payment As P On (B.BillingId=P.BillingId)
Group by B.BillingId


BillingId
AmountPaid (electronic)
AmountAdjusted (adjustment)


12345
73.2800
null

67890
83.5800
30.4300


Warning: Null value is eliminated by an aggregate or other SET operation.