SQL challenges

SPECIALIZED SKILLS on Hackerrank

Solutions of the HackerRank's SQL challenges

1. Basic Select

Challenge	Solution
Revising the Select Query I	MySQL
Revising the Select Query II	MySQL
Select All	MySQL
Select By ID	MySQL
Japanese Cities' Attributes	MySQL
Japanese Cities' Names	MySQL
Weather Observation Station 1	MySQL
Weather Observation Station 3	MySQL
Weather Observation Station 4	MySQL
Weather Observation Station 5	MySQL
Weather Observation Station 6	MySQL
Weather Observation Station 7	MySQL
Weather Observation Station 8	MySQL
Weather Observation Station 9	MySQL
Weather Observation Station 10	MySQL
Weather Observation Station 11	MySQL
Weather Observation Station 12	MySQL
Higher Than 75 Marks	MySQL
Employee Names	MySQL
Employee Salaries	MySQL

2. Advanced Select

Challenge	Solution
Type of Triangle	MySQL
The PADS	MySQL
Occupations	MySQL
Binary Tree Nodes	MySQL
New Companies	MySQL

3. Aggregation Challenges

Challenge	Solution
Revising Aggregations - The Count Function	MySQL
Revising Aggregations - The Sum Function	MySQL
Revising Aggregations - Averages	MySQL
Average Population	MySQL
Japan Population	MySQL
Population Density Difference	MySQL
The Blunder	MySQL
Top Earners	MySQL
Weather Observation Station 2	MySQL
Weather Observation Station 13	MySQL
Weather Observation Station 14	MySQL
Weather Observation Station 15	MySQL
Weather Observation Station 16	MySQL
Weather Observation Station 17	MySQL
Weather Observation Station 18	MySQL
Weather Observation Station 19	MySQL
Weather Observation Station 20	MySQL

4. Basic Join

Challenge	Solution
Asian Population	MySQL
African Cities	MySQL
Average Population of Each Continent	MySQL
The Report	MySQL
Top Competitors	MySQL
Ollivander's Inventory	MySQL
Contest Leaderboard	MySQL

5. Advanced Join

Challenge	Solution
SQL Project Planning	MySQL
Placements	MySQL
Symmetric Pairs	MySQL
Interviews	MySQL
15 Days of Learning SQL	MySQL

6. Alternative Queries

Challenge	Solution
Draw The Triangle 1	MySQL
Draw The Triangle 2	MySQL
Print Prime Numbers	MySQL