SQL Interview Questions Set I
1. What is DBMS?
2. What is RDBMS?
3. What is SQL?
4. What are the different type of SQL’s?
5. What are the Advantages of SQL?
6. What is a field in a database?
7. What is a Record in a database?
8. What is a Table in a database?
9. What is a database transaction?
10. What are properties of a transaction?
11. What is a Database Lock?
12. What are the type of locks?
13. What are the different type of normalization?
14. What is a primary key?
15. What is a Composite Key?
16. What is a Composite Primary Key?
17. What is a Foreign Key?
18. What is a Unique Key?
19. Define SQL Insert Statement?
20. Define SQL Update Statement?
21. Define SQL Delete Statement?
22. What are wild cards used in database for Pattern Matching?
23. Define Join and explain different type of joins?
24. What is Self-Join?
25. What is Cross Join?
26. What is a view?
27. What are the advantages and disadvantages of views in a database?
28. What is a stored procedure?
29. What are the advantages a stored procedure?
30. What is a trigger?
31. Explain the difference between DELETE , TRUNCATE and DROP commands?
32. What is the difference between Cluster and Non cluster Index?
33. What is Union, minus and Interact commands?
34. What is the SQL syntax for sorting, and which is the default order?
35. Write a SQL query to find the largest element in a column.
36. What is the difference between UNION and UNION ALL?
37. What is the difference between JOIN and UNION?
38. What is the difference between WHERE clause and HAVING clause?
39. What is the difference among UNION, MINUS and INTERSECT?
40. How can we transpose a table using SQL (changing rows to column or vice-versa) ?
41. How to generate row number in SQL Without ROWNUM?
42. How to select first 5 records from a table?
43. What is the difference between ROWNUM pseudo column and ROW_NUMBER()
44. What are the differences among ROWNUM, RANK and DENSE_RANK?
45. Write SQL Query to display current date.
46. Write an SQL Query to check whether date passed to Query is date of given format
47. Write SQL Query to find duplicate rows in a database? and then write SQL
query to delete them?
48. When is the UPDATE_STATISTICS command used
49. Explain query execution plan?
50. What is recursion? Is it possible for a stored procedure to call itself or recursive
stored procedure? How many levels of SP nesting is possible?