MariaDB 10.3

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CREATE TABLE sales (
    id int auto_increment primary key,
    customerID VARCHAR(255),
    sales_date DATE,
    sales_volume INT,
    annual_unqiue_count INT
);

INSERT INTO sales
(customerID, sales_date, sales_volume, annual_unqiue_count)
VALUES 
("Customer_01", "2020-03-01", "600", "1"),
("Customer_01", "2020-03-25", "315", "0"),

("Customer_02", "2020-03-18", "208", "1"),
("Customer_02", "2020-07-25", "140", "0"),

("Customer_03", "2020-10-18", "400", "1"),
("Customer_03", "2020-12-06", "500", "0"),
("Customer_03", "2020-12-18", "438", "0"),
("Customer_03", "2020-12-25", "917", "0");

SELECT
customerID,
MONTH(sales_date),
SUM(annual_unqiue_count),
SUM(sales_volume),
  (CASE WHEN annual_unqiue_count <> 0
  THEN SUM(sales_volume) over (PARTITION BY customerId)
  ELSE 0 END) AS sales_volume
FROM sales
GROUP BY 1,2;


customerID
MONTH(sales_date)
SUM(annual_unqiue_count)
SUM(sales_volume)
sales_volume


Customer_01
3
1
915
600

Customer_02
3
1
208
348

Customer_02
7
0
140
0

Customer_03
10
1
400
900

Customer_03
12
0
1855
0


SELECT 
customerID,
MONTH(sales_date) sales_date,
annual_unqiue_count,
sales_volume,
(annual_unqiue_count * SUM(sales_volume) OVER (PARTITION BY customerID)) AS total_sales_volume 
FROM sales;


customerID
sales_date
annual_unqiue_count
sales_volume
total_sales_volume


Customer_01
3
1
600
915

Customer_01
3
0
315
0

Customer_02
7
0
140
0

Customer_02
3
1
208
348

Customer_03
12
0
917
0

Customer_03
10
1
400
2255

Customer_03
12
0
500
0

Customer_03
12
0
438
0


SELECT
t1.customerID,
MONTH(t1.sales_date),
SUM(t1.sales_volume_date)
FROM

  (SELECT
  customerID,
  sales_date,
  SUM(annual_unqiue_count) AS annual_unique_count,
  SUM(sales_volume) AS sales_volume,
    (CASE WHEN annual_unqiue_count <> 0
    THEN SUM(sales_volume) over (PARTITION BY customerId)
    ELSE 0 END) AS sales_volume_date
  FROM sales
  GROUP BY 1,2) t1
  
GROUP BY 1,2;


customerID
MONTH(t1.sales_date)
SUM(t1.sales_volume_date)


Customer_01
3
915

Customer_02
3
348

Customer_02
7
0

Customer_03
10
2255

Customer_03
12
0

customerID	MONTH(sales_date)	SUM(annual_unqiue_count)	SUM(sales_volume)	sales_volume
Customer_01	3	1	915	600
Customer_02	3	1	208	348
Customer_02	7	0	140	0
Customer_03	10	1	400	900
Customer_03	12	0	1855	0