9/15 每日一題(MYSQL 選出欄位low_fats , recyclable 皆等於Y時的product_id )

Table: Products

+-------------+---------+
| Column Name | Type    |
+-------------+---------+
| product_id  | int     |
| low_fats    | enum    |
| recyclable  | enum    |
+-------------+---------+
product_id is the primary key (column with unique values) for this table.
low_fats is an ENUM (category) of type ('Y', 'N') where 'Y' means this product is low fat and 'N' means it is not.
recyclable is an ENUM (category) of types ('Y', 'N') where 'Y' means this product is recyclable and 'N' means it is not.

 

Write a solution to find the ids of products that are both low fat and recyclable.

Return the result table in any order.

The result format is in the following example.

 

Example 1:

Input: 
Products table:
+-------------+----------+------------+
| product_id  | low_fats | recyclable |
+-------------+----------+------------+
| 0           | Y        | N          |
| 1           | Y        | Y          |
| 2           | N        | Y          |
| 3           | Y        | Y          |
| 4           | N        | N          |
+-------------+----------+------------+
Output: 
+-------------+
| product_id  |
+-------------+
| 1           |
| 3           |
+-------------+
Explanation: Only products 1 and 3 are both low fat and recyclable.

 # Write your MySQL query statement below

SELECT

product_id

FROM Products

where product_id IN

(CASE

WHEN  low_fats ='Y' and recyclable ='Y' then  product_id  

END)

---------------------------

# Write your MySQL query statement below
SELECT product_id
FROM Products
WHERE low_fats LIKE 'Y' AND recyclable LIKE 'Y';

-----------------------------

# Write your MySQL query statement below
SELECT product_id
FROM Products
WHERE low_fats = 'Y' AND recyclable = 'Y'