Hackerrank-SQL



Hackerrank SQL Solutions

My solutions of Hackerrank SQL challenges. This repository is mainly for my practice and future references, but anyone can use it for learning.

Domains

Basic Select Challenges

Number Challenges Solutions
1 Revising the Select Query I SQL
2 Revising the Select Query II SQL
3 Select All SQL
4 Select By ID SQL
5 Japanese Cities' Attributes SQL
6 Japanese Cities' Names SQL
7 Weather Observation Station 1 SQL
8 Weather Observation Station 3 SQL
9 Weather Observation Station 4 SQL
10 Weather Observation Station 5 SQL
11 Weather Observation Station 6 SQL
12 Weather Observation Station 7 SQL
13 Weather Observation Station 8 SQL
14 Weather Observation Station 9 SQL
15 Weather Observation Station 10 SQL
16 Weather Observation Station 11 SQL
17 Weather Observation Station 12 SQL
18 Higher Than 75 Marks SQL
19 Employee Names SQL
20 Employee Salaries SQL

Advanced Select Challenges

Number Challenges Solutions
1 Type of Triangle SQL
2 The PADS SQL
3 Occupations SQL
4 Binary Tree Nodes SQL
5 New Companies SQL

Aggregation

Number Challenges Solutions
1 Revising Aggregations - The Count Function SQL
2 Revising Aggregations - The Sum Function SQL
3 Revising Aggregations - Averages Function SQL
4 Average Population SQL
5 Japan Population SQL
6 Population Density Difference SQL
7 The Blunder SQL
8 Top Earners SQL
9 Weather Observation Station 2 SQL
10 Weather Observation Station 13 SQL
11 Weather Observation Station 14 SQL
12 Weather Observation Station 15 SQL
13 Weather Observation Station 16 SQL
14 Weather Observation Station 17 SQL
15 Weather Observation Station 18 SQL
16 Weather Observation Station 19 SQL
17 Weather Observation Station 20 SQL

Basic Join

Number Challenges Solutions
1 Asian Population SQL
2 African Cities SQL
3 Average Population of Each Continent SQL
4 The Report SQL
5 Top Competitors SQL
6 Inventory SQL
7 Challenges SQL
8 Contest Leaderboard SQL

Advanced Join

Number Challenges Solutions
1 SQL Project Planning SQL
2 Placements SQL
3 Symmetric Pairs SQL

Alternative Queries

Number Challenges Solutions
1 Draw The Triangle 1 SQL
2 Draw The Triangle 2 SQL