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SQL
SQL interview questions
Classic interview patterns from every topic.
0
/ 57 solved
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Basic (5)
Intermediate (12)
Advanced (40)
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1
Backup before a risky change
Interview
Advanced
2
Valid Indian mobile numbers
Interview
Advanced
3
Library design
Interview
Advanced
4
Keep the latest record
Interview
Advanced
5
Monthly summary table
Interview
Advanced
6
View of department KPIs
Interview
Advanced
7
Long-serving and well paid
Interview
Advanced
8
Second highest salary
Interview
Advanced
9
Top 3 with ties
Interview
Advanced
10
Revenue by category
Interview
Advanced
11
Average order value
Interview
Advanced
12
Above the company average
Interview
Advanced
13
Duplicate emails, case-insensitive
Interview
Advanced
14
Departments without staff
Interview
Basic
15
Products never ordered
Interview
Basic
16
Sold below list price
Interview
Advanced
17
Customers who bought both
Interview
Advanced
18
Employee and manager
Interview
Basic
19
Earns more than the manager
Interview
Intermediate
20
Skip-level manager
Interview
Advanced
21
Consecutive-day logins
Interview
Advanced
22
Above the average
Interview
Basic
23
Above their department average
Interview
Intermediate
24
Nth highest salary
Interview
Advanced
25
Org chart levels
Interview
Advanced
26
Fill missing months
Interview
Advanced
27
Repeat purchase rate
Interview
Advanced
28
Cohort retention
Interview
Advanced
29
Pivot with CASE
Interview
Intermediate
30
Fee status report
Interview
Advanced
31
Flag suspicious transactions
Interview
Advanced
32
NOT IN trap
Interview
Intermediate
33
Fill gaps with the previous value
Interview
Advanced
34
Clean phone numbers
Interview
Advanced
35
Most common first letter
Interview
Advanced
36
Month-over-month growth
Interview
Advanced
37
Fiscal year
Interview
Advanced
38
Login streaks
Interview
Advanced
39
Top earner per department
Interview
Intermediate
40
Top 2 per department
Interview
Intermediate
41
Remove duplicates with ROW_NUMBER
Interview
Intermediate
42
Nth highest with DENSE_RANK
Interview
Advanced
43
Month-over-month change
Interview
Intermediate
44
3-month moving average
Interview
Intermediate
45
Account balance
Interview
Intermediate
46
Growth streaks
Interview
Advanced
47
Cumulative share (Pareto)
Interview
Advanced
48
Sessions from logins
Interview
Advanced
49
Symmetric difference
Interview
Advanced
50
Compare two table versions
Interview
Advanced
51
Best customers report
Interview
Basic
52
Month-wise new vs returning customers
Interview
Intermediate
53
Frequently bought together
Interview
Intermediate
54
Customer lifetime summary
Interview
Advanced
55
Churned customers
Interview
Advanced
56
Second purchase conversion
Interview
Advanced
57
Executive dashboard row
Interview
Advanced