id int auto_increment primary key,

time_stamp TIMESTAMP,

product VARCHAR(255),

sales_quantity INT

);

INSERT INTO sales

(time_stamp, product, sales_quantity)

VALUES

("2020-01-14 07:15:30", "Product_A", "100"),

("2020-01-14 07:15:30", "Product_B", "300"),

("2020-01-14 07:18:45", "Product_A", "200"),

("2020-01-14 07:18:45", "Product_B", "900"),

("2020-01-15 07:19:23", "Product_A", "400"),

("2020-01-15 07:19:23", "Product_B", "270"),

("2020-01-15 07:45:10", "Product_A", "900"),

("2020-01-15 07:45:10", "Product_B", "340");

DATE(s.time_stamp) time_stamp,

FIRST_VALUE(SUM(s.sales_quantity)) OVER (PARTITION BY DATE(s.time_stamp) ORDER BY s.time_stamp DESC) sales_quantity

FROM sales s

GROUP BY s.time_stamp;