MySQL 8.0

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CREATE TABLE products (
  `id` INTEGER Primary Key,
  `name` VARCHAR(6),
  `deleted_at` VARCHAR(4)
);

INSERT INTO products
  (`id`, `name`, `deleted_at`)
VALUES
  ('2', 'Apple', 'null'),
  ('5', 'Banana', 'null'),
  ('6', 'Pear', 'null');



CREATE TABLE Orders (
  `id` INTEGER PRIMARY KEY,
  `sale_date` DATE
);

INSERT INTO Orders
  (`id`, `sale_date`)
VALUES
  ('1', '2021-02-12'),
  ('2', '2021-02-12');

CREATE TABLE ProductOrders (
  `order_id` INTEGER,
  `product_id` VARCHAR(18),
  `quantity` INTEGER,
  `price` DECIMAL(10,2)
);

INSERT INTO ProductOrders
  (`order_id`, `product_id`, `quantity`, `price`)
VALUES
  ('1', '2', '2', '2.50'),
  ('1', '5', '3', '3.50'),
  ('2', '2', '1', '2.00'),
  ('2', '5', '3', '3.50');
SELECT
    p.id AS prod_id,
    p.name AS prod_name,
    sum(po.quantity) AS quantity_sold
FROM products p
    LEFT JOIN (ProductOrders AS po 
    INNER JOIN (SELECT * FROM Orders WHERE sale_date = '2021-02-12') AS o ON po.order_id  = o.id)
    ON p.id = po.product_id
GROUP BY p.id, p.name,po.price
ORDER BY p.name;


prod_id
prod_name
quantity_sold


2
Apple
1

2
Apple
2

5
Banana
6

6
Pear
null


SELECT
    p.id AS prod_id,
    p.name AS prod_name,
    sum(po.quantity) AS quantity_sold
FROM products p
    LEFT JOIN (ProductOrders AS po 
    INNER JOIN (SELECT * FROM Orders WHERE sale_date = '2021-02-13') AS o ON po.order_id  = o.id)
    ON p.id = po.product_id
GROUP BY p.id, p.name,po.price
ORDER BY p.name;


prod_id
prod_name
quantity_sold


2
Apple
null

5
Banana
null

6
Pear
null