SQl Interview Quetions

1. Explain the order of execution of SQL.
2. What is the difference between where and having?
3. What is the use of a group by?
4. Explain all types of joins in SQL?
5. What are triggers in SQL?
6. What is the stored procedure in SQL
7. Explain all types of window functions? (Mainly rank, row_num, dense_rank, lead & lag)
8. What is difference between Delete and Truncate?
9. What is difference between DML, DDL and DCL?
10. What are aggregate function and when do we use them? explain with few example.
11. Which is faster between CTE and Subquery?
12. What are constraints and types of Constraints?
13. Types of Keys?
14. Different types of Operators ?
15. Difference between Group By and Where?
16. What are Views?
17. What are different types of constraints?
18. What is difference between varchar and nvarchar?
19. Similar for char and nchar?
20. What are index and their types?
21. What is an index? Explain its different types.
22. List the different types of relationships in SQL.
23. Differentiate between UNION and UNION ALL.
24. How many types of clauses in SQL ?
25. What is the difference between UNION and UNION ALL in SQL?
26. What are the various types of relationships in SQL?
27. Difference between Primary Key and Secondary Key?
28. What is the difference between where and having?
29. Find the second highest salary of an employee?
30. Write retention query in SQL?
31. Write year-on-year growth in SQL?
32. Write a query for cummulative sum in SQL?
33. Difference between Function and Store procedure ?
34. Do we use variable in views?
35. What are the limitations of views?