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Joins Interview Problems (30)

Practice joins questions asked in data science interviews

Status Title Difficulty
All Students Including Those Not Enrolled Pro Easy
Find Customers With Their Orders Pro Easy
Inner Join Orders and Customers Free Easy
Left Join to Find Missing Reviews Pro Easy
List All Employees and Their Department Names Pro Easy
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Match Shippers to Orders Pro Easy
Multi-Table Join with Quantities Pro Easy
Products With No Sales Pro Easy
Show Tags for Each Article Pro Easy
Simulate RIGHT JOIN: All Departments With Their Employees Pro Easy
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Cross Join for Combinations Pro Medium
Customers Who Ordered Every Product Category Pro Medium
Departments With Average Salary Above Threshold Pro Medium
Employee Manager Join Free Medium
Employee Project Assignments With Department Pro Medium
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Full Outer Join Simulation Pro Medium
Order Details: Customer, Order, and Product Pro Medium
Self Join to Find Employee Pairs in Same Department Pro Medium
Simulate RIGHT JOIN: All Products Including Unsold Pro Medium
Students, Courses, and Their Instructors Pro Medium
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Total Spend Per Customer Pro Medium
Unmatched Records: Orders Without Customers Pro Medium
Hierarchical Self Join for Org Chart Pro Hard
Join with Aggregation and Filtering Pro Hard
Latest Order Per Customer Using Join and Subquery Pro Hard
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