SQL in Oracle Interview Questions

  1. What is a cursor?
  2. What is OCI. What are its uses?
  3. What is the purpose of a cluster?
  4. Display the number value in Words?
  5. Which is more faster – IN or EXISTS?
  6. Display the records between two range?
  7. What are different Oracle database objects?
  8. Is there a limit on the size of a PL/SQL block?
  9. What is difference between Rename and Alias?
  10. Can a function take OUT parameters if not why?
  11. What is difference between SUBSTR and INSTR?
  12. What is difference between SQL and SQL*PLUS?
  13. How to find out nth highest salary from emp table?
  14. Can a primary key contain more than one columns?
  15. How you will avoid your query from using indexes?
  16. Explain Difference between procedure and function?
  17. What is implicit cursor and how is it used by Oracle?
  18. What WHERE CURRENT OF clause does in a cursor?
  19. How you were passing cursor variables in PL/SQL 2.2?
  20. How will you delete duplicating rows from a base table?
  21. Which data type is used for storing graphics and images?
  22. Difference between database triggers and form triggers?
  23. Can the default values be assigned to actual parameters?
  24. What are various joins used while writing SUBQUERIES?
  25. Explain what is difference between SUBSTR and INSTR?
  26. Can you use a commit statement within a database trigger?
  27. Explain difference between an implicit and an explicit cursor?
  28. How you open and close a cursor variable. Why it is required?
  29. What is difference between a formal and an actual parameter?
  30. Whet are the difference between primary key and foreign key?
  31. Explain which data type is used for storing graphics and images?
  32. What are various privileges that a user can grant to another user?
  33. The maximum number of columns a table can have in oracle SQL?
  34. What is difference between UNIQUE and PRIMARY KEY constraints?
  35. When do you use WHERE clause and when do you use HAVING clause?
  36. What are different modes of parameters used in functions and procedures?
  37. There is a % sign in one field of a column. What will be the query to find it?
  38. What is an UTL_FILE.What are different procedures and functions associated with it?
  39. What should be the return type for a cursor variable. Can we use a scalar data type as return type?
  40. What is the maximum buffer size that can be specified using the DBMS_OUTPUT.ENABLE function?