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Master SQL 50

Essential SQL queries for database interview preparation.

SQLSelect

1908. Recyclable and Low Fat Products
SolutionEASY
584. Find Customer Referee
SolutionEASY
595. Big Countries
SolutionEASY
1258. Article Views I
SolutionEASY
1827. Invalid Tweets
SolutionEASY

SQLBasic Joins

1509. Replace Employee ID With The Unique Identifier
SolutionEASY
1153. Product Sales Analysis I
SolutionEASY
1724. Customer Who Visited but Did Not Make Any Transactions
SolutionEASY
197. Rising Temperature
SolutionEASY
1801. Average Time of Process per Machine
SolutionEASY
577. Employee Bonus
SolutionEASY
1415. Students and Examinations
SolutionEASY
570. Managers with at Least 5 Direct Reports
SolutionMEDIUM
2087. Confirmation Rate
SolutionMEDIUM

SQLBasic Aggregate Functions

620. Not Boring Movies
SolutionEASY
1390. Average Selling Price
SolutionEASY
1161. Project Employees I
SolutionEASY
1773. Percentage of Users Attended a Contest
SolutionEASY
1338. Queries Quality and Percentage
SolutionEASY
1317. Monthly Transactions I
SolutionMEDIUM
1292. Immediate Food Delivery II
SolutionMEDIUM
1182. Game Play Analysis IV
SolutionMEDIUM

SQLSorting and Grouping

2495. Number of Unique Subjects Taught by Each Teacher
SolutionEASY
1245. User Activity for the Past 30 Days I
SolutionEASY
1155. Product Sales Analysis III
SolutionMEDIUM
596. Classes More Than 5 Students
SolutionEASY
1877. Find Followers Count
SolutionEASY
619. Biggest Single Number
SolutionEASY
1135. Customers Who Bought All Products
SolutionMEDIUM

SQLAdvanced Select and Joins

1882. The Number of Employees Which Report to Each Employee
SolutionEASY
1942. Primary Department for Each Employee
SolutionEASY
610. Triangle Judgement
SolutionEASY
180. Consecutive Numbers
SolutionMEDIUM
1278. Product Price at a Given Date
SolutionMEDIUM
1327. Last Person to Fit in the Bus
SolutionMEDIUM
2057. Count Salary Categories
SolutionMEDIUM

SQLSubqueries

2127. Employees Whose Manager Left the Company
SolutionEASY
626. Exchange Seats
SolutionMEDIUM
1480. Movie Rating
SolutionMEDIUM
1452. Restaurant Growth
SolutionMEDIUM
602. Friend Requests II: Who Has the Most Friends
SolutionMEDIUM
585. Investments in 2016
SolutionMEDIUM
185. Department Top Three Salaries
SolutionHARD

SQLAdvanced String Functions / Regex / Clause

1811. Fix Names in a Table
SolutionEASY
1670. Patients With a Condition
SolutionEASY
196. Delete Duplicate Emails
SolutionEASY
176. Second Highest Salary
SolutionMEDIUM
1625. Group Sold Products By The Date
SolutionEASY
1462. List the Products Ordered in a Period
SolutionEASY
1664. Find Users With Valid E-Mails
SolutionEASY

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