sales-analysis-iii.sql

-- Table: Product

-- +--------------+---------+
-- | Column Name  | Type    |
-- +--------------+---------+
-- | product_id   | int     |
-- | product_name | varchar |
-- | unit_price   | int     |
-- +--------------+---------+
-- product_id is the primary key of this table.
-- Table: Sales

-- +-------------+---------+
-- | Column Name | Type    |
-- +-------------+---------+
-- | seller_id   | int     |
-- | product_id  | int     |
-- | buyer_id    | int     |
-- | sale_date   | date    |
-- | quantity    | int     |
-- | price       | int     |
-- +------ ------+---------+
-- This table has no primary key, it can have repeated rows.
-- product_id is a foreign key to Product table.
 

-- Write an SQL query that reports the products that were only sold in spring 2019. That is, between 2019-01-01 and 2019-03-31 inclusive.

-- The query result format is in the following example:

-- Product table:
-- +------------+--------------+------------+
-- | product_id | product_name | unit_price |
-- +------------+--------------+------------+
-- | 1          | S8           | 1000       |
-- | 2          | G4           | 800        |
-- | 3          | iPhone       | 1400       |
-- +------------+--------------+------------+

-- Sales table:
-- +-----------+------------+----------+------------+----------+-------+
-- | seller_id | product_id | buyer_id | sale_date  | quantity | price |
-- +-----------+------------+----------+------------+----------+-------+
-- | 1         | 1          | 1        | 2019-01-21 | 2        | 2000  |
-- | 1         | 2          | 2        | 2019-02-17 | 1        | 800   |
-- | 2         | 2          | 3        | 2019-06-02 | 1        | 800   |
-- | 3         | 3          | 4        | 2019-05-13 | 2        | 2800  |
-- +-----------+------------+----------+------------+----------+-------+

-- Result table:
-- +-------------+--------------+
-- | product_id  | product_name |
-- +-------------+--------------+
-- | 1           | S8           |
-- +-------------+--------------+
-- The product with id 1 was only sold in spring 2019 while the other two were sold after.

# V0 
SELECT product_id, 
       product_name 
FROM   product 
WHERE  product_id NOT IN (SELECT product_id 
                          FROM   sales 
                          WHERE  sale_date NOT BETWEEN 
                                 '2019-01-01' AND '2019-03-31'); 

# V1
# https://circlecoder.com/sales-analysis-III/
select p.product_id, p.product_name
from Product p
left join Sales s
on p.product_id = s.product_id
group by p.product_id
having sum(s.sale_date between '2019-01-01' and '2019-03-31') = count(s.sale_date)

# V2 
# Time:  O(m + n)
# Space: O(m + n)
SELECT product_id, 
       product_name 
FROM   product 
WHERE  product_id NOT IN (SELECT product_id 
                          FROM   sales 
                          WHERE  sale_date NOT BETWEEN 
                                 '2019-01-01' AND '2019-03-31');