Shalini's Bank of Interview Questions

Database:

1. What are the different types of joins? Where do you use joins?
2. How do  you delete duplicate rows from a table? 
3. What are the trade-offs you face while using indexes?
4. How do you define a union?
5. What is the difference between "dropping" a table and "truncating" a table?
6. What is a “trigger”? 
7. What is a “transaction”? Why are they necessary?
8.  What is a "view"? How do you get the script for a view?
9. What is the difference between VARCHAR and VARCHAR2 datatypes?
10. What is the structure of a typical stored procedure?
11. Explain normalization with regards to database design.
12. What pitfalls should you avoid while creating a primary key?
13. What is the difference between “translate” and “replace”?
14.  What is a cursor and how do you use it to retrieve multiple RecordSets? 
15. What is the difference between a “where” clause and a “having” clause? 
16. What are the benefits of using a "group by" clause?
17. Why can a “group by” or “order by” clause be expensive to process?  
18. Which are the common functions that are provided to you? (TO_DATE, MAX, MIN etc)
19. What is the difference between a “procedure” and a “function”? 
20. How can you copy the structure of a table without copying the data? 
21. How to find out the database name from SQL*PLUS command prompt? 
22. What are the different types of constraints? Why are they used and how? 
23. When do you get constraint violation? 
24. What does "Aggregate Key" denote?
25. How do you handle exceptional situations in SQL?(RAISE ERROR)
26. What are analytical functions?
27. 
    
    
    
    What does “null" mean in Oracle?