Practice SQL Scripts From Interview Prep Websites

These are scripts that answer questions from leetcode, DataLemur, hackerank and sqlzoo. Links to questions and my answers are below!

LeetCode

Question	Answer
Employees earn more than their managers	Solution
Second highest salaries	Solution
Customers who never order	Solution
Duplicate Emails	Solution
Rising Temperatures	Solution
Department Top Three Salaries	Solution
N-th Highest Salary	Solution
Department Highest Salary	Solution
Monthly Transactions I	Solution
Managers with at Least 5 Direct Reports	Solution
Rank Scores	Solution
Not Boring Movies	Solution
Exchange Seats	Solution
Consecutive Numbers	Solution
Human Traffice Of Stadium	Solution
Trips and Users	Solution
Capital Gains/Loss	Solution
Market Analysis I	Solution
Tree Node	Solution
Restaurant Growth	Solution
Game Play Analysis I	Solution
Game Play Analysis IV	Solution
Investments In 2016	Solution
Friend Requests II: Who Has the Most Friends	Solution
Odd And Even Transactions	Solution
Confirmation Rate	Solution

Question	Answer
Laptop vs. Mobile Viewership	Solution
Average Review Ratings	Solution
Matching Skills	Solution
Odd and Even Measurements	Solution
Y-on-Y Growth Rate	Solution
Page With No Likes	Solution
Frequently Purchased Pairs	Solution
Supercloud Customer	Solution
Sending vs. Opening Snap	Solution
User's Third Transaction	Solution
Repeated Payments	Solution
Compressed Mode	Solution
Signup Activation Rate	Solution
Highest-Grossing Items	Solution
Top 5 Artists	Solution
International Call Percentage	Solution
Tweets' Rolling Average	Solution
Top Three Salaries	Solution
Histogram of Users and Purchases	Solution

Question	Answer
Japanese Cities	Solution
Earnings of employees	Solution
Weather Observation Station 8	Soluton
Weather Observation Station 9	Soluton
More Than 75 Marks	Solution
The Pads	Solution
Binary Search Tree 1	Solution

Question	Answer
Richer Than UK	Solution
Bigger Than Every Country In Europe	Solution
Neighbours of Argentina and Australia	Solution
Teams that have coach Fernando Santos	Solution
Busy years for John Travolta	Solution