1757 - Recyclable and Low Fat Products
SELECT product_id
FROM Products
WHERE low_fats = 'Y'
AND recyclable = 'Y'
584 - Find Customer Referee
SELECT name
FROM Customer
WHERE referee_id != 2 OR referee_id IS null
595 - Big Countries
SELECT name, population, area
FROM WORLD
WHERE area >= 3000000
OR population >= 25000000
1148 - Article Views I
SELECT DISTINCT author_id as id
FROM Views
WHERE viewer_id >= 1
AND author_id = viewer_id
ORDER BY author_id
1683 - Invalid Tweets
SELECT tweet_id
FROM Tweets
WHERE length(content) > 15
1378 - Replace Employee ID With The Unique Identifier
SELECT unique_id, name
FROM Employees e
LEFT JOIN EmployeeUNI eu
ON e.id = eu.id
1068 - Product Sales Analysis I
SELECT product_name, year, price
FROM Sales s
LEFT JOIN Product p
ON s.product_id = p.product_id
1581 - Customer Who Visited but Did Not Make Any Transactions
SELECT customer_id, COUNT(*) as count_no_trans
FROM Visits
WHERE visit_id NOT IN (SELECT DISTINCT visit_id FROM Transactions)
GROUP BY customer_id