TOP 100 SQL SERVER INTERVIEW QUESTIONS

SQL SERVER INTERVIEW QUESTIONS

1.      What is the Complex task that you handled in your project

2.      What are the differences between Delete and Truncate?

3.      Diff b/w Char and Varchar

4.      Diff b/w Unicode and Non-unicode characters

5.      Different ways to identify duplicate records in table

6.      How will you identify table granularity if we table doesn’t have any primary key/unique key

7.      Diff b/w Stored procedure and Function

8.      How parameter sniffing will happen? Give me one example

9.      Can we embed Dynamic SQL in Functions

10. Diff b/w CROSS Apply and Outer Apply and different from INNER JOIN and OUTER JOINS

11. Brief about Windows Functions which were introduced as part of SQL Server 2012

12. Diff b/w Coalesce() and ISNULL() and which will be best?

13. How many clustered and non clustered indexes can be created in one table?

14. What are the main differences between UNION ,  UNION ALL and EXCEPT

15. How will identify the root causes of slow running procedures/functions

16. How will you identify slow running queries in SQL Server

17. How will identify the matched and non matched records between two tables 

18. What are ACID properties

19. What are the isolation levels and explain each one with example

20. What is the diff b/w LOCK and NOLOCK

21. What is Table variable, Temp  table and CTE and in which scenarios what kind of table will you use

22. Explain the scenario where you have written normal subquery and Correlated Subquery

23. Diff b/w Where and Having Clause

24. Can we execute Stored Procedure inside Function?

25.  Can we you use Case Statement in Order by Clause?

26. Explain about INNER, LEFT, RIGHT, FULL OUTER joins

27. Explain the scenario where you have used Self join

28. What are deleted and inserted tables

29. Explain the scenario where MERGE statement will be use ful

30. How will you reseed the identity column

31. How will you check if column exists for a table or view in database

32. What is trigger and different types of triggers

33. What is view and indexed view/materialised view

34. What is the Query logical execution order

35. Difference between clustered and non clustered index

36. Difference between Stuff and Replace function

37. What is linked Server

38. Difference b/w Varchar and Varchar(max)

39. What are the system databases (master, msdb, model and tempdb) roles and functionalities

40. Difference b/w index seek and index scan

41. Difference b/w RaiseError and throw and which one will be the best to use

42. Pivot and Unpivot

43. Diff b/w IN and EXISTS clause

44. What is cursor and how many different types are there

45. What is exception handling

46. What are dirty reads, phantom reads

47. What is dead lock

48. Diff b/w Local and Global Temporary tables

49. What is synonym

50. What is Sequence? Diff b/w Sequence and Identity