_1083.sql

--1083. Sales Analysis II
--
--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 buyers who have bought S8 but not iPhone. Note that S8 and iPhone are products present in the Product table.
--
--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         | 1          | 3        | 2019-06-02 | 1        | 800   |
--| 3         | 3          | 3        | 2019-05-13 | 2        | 2800  |
--+-----------+------------+----------+------------+----------+-------+
--
--Result table:
--+-------------+
--| buyer_id    |
--+-------------+
--| 1           |
--+-------------+
--The buyer with id 1 bought an S8 but didn't buy an iPhone. The buyer with id 3 bought both.

--# Write your MySQL query statement below
select distinct buyer_id from Sales s
join Product p
on p.product_id = s.product_id
where p.product_name = 'S8'
and buyer_id not in
(
select buyer_id from Sales s
    join Product p on p.product_id = s.product_id
    where p.product_name = 'iPhone'
)