SQL

📚 SQL Practice Sheets

📌 SQL Course Progress

Platform	Course	Solution File
LeetCode	top-sql-50
Hackerrank	SQL

📌 SQL Solutions

#	Question Title	Difficulty	Soln	Status
1	Recyclable and Low Fat Products	🟢	🏷️	✅
2	Find Customer Referee	🟢	🏷️	✅
3	Big Countries	🟢	🏷️	✅
4	Article Views I	🟢	🏷️	✅
5	Invalid Tweets	🟢	🏷️	✅

📌 Basic Joins

#	Question Title	Difficulty	Soln	Status
1	Replace Employee ID With The Unique Identifier	🟢	🏷️	✅
2	Product Sales Analysis I	🟢	🏷️	✅
3	Customer Who Visited but Did Not Make Any Transactions	🟢	🏷️	✅
4	Rising Temperature	🟢	🏷️	✅
5	Average Time of Process per Machine	🟢	🏷️	✅
6	Employee Bonus	🟢	🏷️	✅
7	Students and Examinations	🟢	🏷️	✅
8	Managers with at Least 5 Direct Reports	🟡	🏷️
9	Confirmation Rate	🟡	🏷️

📌Basic Aggregate Functions

#	Question Title	Difficulty	Soln	Status
1	Not Boring Movies	🟢	🏷️
2	Average Selling Price	🟢	🏷️
3	Project Employees I	🟢	🏷️
4	Percentage of Users Attended a Contest	🟢	🏷️
5	Queries Quality and Percentage	🟢	🏷️
6	Monthly Transactions I	🟡	🏷️
7	Immediate Food Delivery II	🟡	🏷️
8	Game Play Analysis IV	🟡	🏷️

📌 Sorting and Grouping SQL Solutions

#	Question Title	Difficulty	Soln	Status
1	Number of Unique Subjects Taught by Each Teacher	🟢	🏷️	-
2	User Activity for the Past 30 Days I	🟢	🏷️	-
3	Product Sales Analysis III	🟡	🏷️	-
4	Classes More Than 5 Students	🟢	🏷️	-
5	Find Followers Count	🟢	🏷️	-
6	Biggest Single Number	🟢	🏷️	-
7	Customers Who Bought All Products	🟡	🏷️	-

📌 Advanced Select and Joins SQL Solutions

#	Question Title	Difficulty	Soln	Status
1	The Number of Employees Which Report to Each Employee	🟢	🏷️	-
2	Primary Department for Each Employee	🟢	🏷️	-
3	Triangle Judgement	🟢	🏷️	-
4	Consecutive Numbers	🟡	🏷️	-
5	Product Price at a Given Date	🟡	🏷️	-
6	Last Person to Fit in the Bus	🟡	🏷️	-
7	Count Salary Categories	🟡	🏷️	-

📌 Subqueries

#	Question Title	Difficulty	Soln	Status
1	Employees Whose Manager Left the Company	🟢	🏷️	-
2	Exchange Seats	🟡	🏷️	-
3	Movie Rating	🟡	🏷️	-
4	Restaurant Growth	🟡	🏷️	-
5	Friend Requests II: Who Has the Most Friends	🟡	🏷️	-
6	Investments in 2016	🟡	🏷️	-
7	Department Top Three Salaries	🔴	🏷️	-

📌 Advanced String Functions / Regex / Clause

#	Question Title	Difficulty	Soln	Status
1	Fix Names in a Table		🏷️	-
1	Patients With a Condition		🏷️	-
1	Delete Duplicate Emails		🏷️	-
1	Second Highest Salary		🏷️	-
1	Group Sold Products By The Date		🏷️	-
1	List the Products Ordered in a Period		🏷️	-
1	Find Users With Valid E-Mails		🏷️	-