SQL Server 2019

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CREATE TABLE [dbo].[Payment](
	[PaymentId] [int] NOT NULL,
	[ContractID] [int] NULL,
	[PaymentDate] [datetime] NULL,
	[PaymentAmount] [decimal](18, 2) NULL,
 CONSTRAINT [PK_Payment] PRIMARY KEY CLUSTERED 
(
	[PaymentId] ASC
)WITH (PAD_INDEX  = OFF, STATISTICS_NORECOMPUTE  = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS  = ON, ALLOW_PAGE_LOCKS  = ON) ON [PRIMARY]
) ON [PRIMARY];
INSERT INTO Payment(PaymentId, ContractID, PaymentDate, PaymentAmount)
VALUES (1,	1111,	'2022-01-20 00:00:00.000',	200.00);
INSERT INTO Payment(PaymentId, ContractID, PaymentDate, PaymentAmount)
VALUES (2,	1111,	'2022-02-01 00:00:00.000',	300.00)
INSERT INTO Payment(PaymentId, ContractID, PaymentDate, PaymentAmount)
VALUES (3,	1113,	'2022-01-20 00:00:00.000',	50.00)
INSERT INTO Payment(PaymentId, ContractID, PaymentDate, PaymentAmount)
VALUES (4,	1113,	'2022-01-25 00:00:00.000',	50.00)
INSERT INTO Payment(PaymentId, ContractID, PaymentDate, PaymentAmount)
VALUES (5,	1113,	'2022-02-04 00:00:00.000',	100.00)
INSERT INTO Payment(PaymentId, ContractID, PaymentDate, PaymentAmount)
VALUES (6,	1115,	'2022-02-20 00:00:00.000',	50.00)

6 rows affected

CREATE TABLE [dbo].[Sales](
	[ContractID] [int] NOT NULL,
	[SoldDate] [datetime] NULL,
	[SoldAmount] [decimal](18, 2) NULL,
 CONSTRAINT [PK_Sales] PRIMARY KEY CLUSTERED 
(
	[ContractID] ASC
)WITH (PAD_INDEX  = OFF, STATISTICS_NORECOMPUTE  = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS  = ON, ALLOW_PAGE_LOCKS  = ON) ON [PRIMARY]
) ON [PRIMARY]

INSERT INTO Sales(ContractID, SoldDate, SoldAmount)
VALUES(1111,	'2022-01-01 00:00:00.000',	800.00);
INSERT INTO Sales(ContractID, SoldDate, SoldAmount)
VALUES(1112, 	'2022-01-04 00:00:00.000',	1000.00);
INSERT INTO Sales(ContractID, SoldDate, SoldAmount)
VALUES(1113, 	'2022-01-04 00:00:00.000',	500.00);
INSERT INTO Sales(ContractID, SoldDate, SoldAmount)
VALUES(1114, 	'2022-01-05 00:00:00.000',	200.00);
INSERT INTO Sales(ContractID, SoldDate, SoldAmount)
VALUES(1115, 	'2022-02-10 00:00:00.000',	100.00);
5 rows affected

SELECT * FROM Payment


PaymentId
ContractID
PaymentDate
PaymentAmount


1
1111
2022-01-20 00:00:00.000
200.00

2
1111
2022-02-01 00:00:00.000
300.00

3
1113
2022-01-20 00:00:00.000
50.00

4
1113
2022-01-25 00:00:00.000
50.00

5
1113
2022-02-04 00:00:00.000
100.00

6
1115
2022-02-20 00:00:00.000
50.00


SELECT * FROM Sales


ContractID
SoldDate
SoldAmount


1111
2022-01-01 00:00:00.000
800.00

1112
2022-01-04 00:00:00.000
1000.00

1113
2022-01-04 00:00:00.000
500.00

1114
2022-01-05 00:00:00.000
200.00

1115
2022-02-10 00:00:00.000
100.00


WITH cte_quantity
AS
(
SELECT
    PaymentMonth,
    SoldAmount,
    [1] AS Jan,
    [2] AS Feb,
    [3] AS Mrz,
    [4] AS Apr,
    [5] AS Mai,
    [6] AS Jun,
    [7] AS Jul,
    [8] AS Aug,
    [9] AS Sep,
    [10] AS Okt,
    [11] AS Nov,
    [12] AS Dez
FROM
(
Select
--S.ContractID ,
MONTH(S.SoldDate) as  SoldMonth,
MONTH(P.PaymentDate) as PaymentMonth,
SUM(S.SoldAmount) as SoldAmount, 
SUM(P.PaymentAmount) as PaymentAmount
from Sales S
INNER JOIN Payment P ON S.ContractID = P.ContractID 
GROUP BY 
MONTH(S.SoldDate), 
MONTH(P.PaymentDate) 
  ) source
PIVOT
(
   -- SUM(SoldAmount)  
    SUM(PaymentAmount)
    FOR SoldMonth
    IN ( [1], [2], [3], [4], [5], [6], [7], [8], [9], [10], [11], [12] )
) AS pvtMonth
)
 
SELECT
 PaymentMonth, 
 SUM(SoldAmount) AS Sold,
 sum(Jan)as Jan , sum(Feb) as Feb, sum(Mrz) as Mrz, sum(Apr) as Apr, sum(Mai) as Mai, 
 sum(Jun)as Jun , sum(Jul) as Jul, sum(Aug) as Aug, sum(Sep) as Sep, sum(Okt) as Okt,
 sum(Nov) as Nov, sum(Dez) as Dez   
FROM cte_quantity
GROUP BY PaymentMonth


PaymentMonth
Sold
Jan
Feb
Mrz
Apr
Mai
Jun
Jul
Aug
Sep
Okt
Nov
Dez


1
1800.00
300.00
null
null
null
null
null
null
null
null
null
null
null

2
1400.00
400.00
50.00
null
null
null
null
null
null
null
null
null
null


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

PaymentMonth	Sold	Jan	Feb	Mrz	Apr	Mai	Jun	Jul	Aug	Sep	Okt	Nov	Dez
1	1800.00	300.00	null	null	null	null	null	null	null	null	null	null	null
2	1400.00	400.00	50.00	null	null	null	null	null	null	null	null	null	null

PaymentId	ContractID	PaymentDate	PaymentAmount
1	1111	2022-01-20 00:00:00.000	200.00
2	1111	2022-02-01 00:00:00.000	300.00
3	1113	2022-01-20 00:00:00.000	50.00
4	1113	2022-01-25 00:00:00.000	50.00
5	1113	2022-02-04 00:00:00.000	100.00
6	1115	2022-02-20 00:00:00.000	50.00

ContractID	SoldDate	SoldAmount
1111	2022-01-01 00:00:00.000	800.00
1112	2022-01-04 00:00:00.000	1000.00
1113	2022-01-04 00:00:00.000	500.00
1114	2022-01-05 00:00:00.000	200.00
1115	2022-02-10 00:00:00.000	100.00