Top Oracle SQL PLSQL Interview Questions – Must Prepare

The list of best and top Oracle SQL PLSQL interview questions for experienced professionals and freshers real time. Must prepare list of questions and find your answers please.


SQL Questions

1. What is SDLC cycle? Please explain.
2. What are Codd’s rules? Please explain.
3. What is normalization and explain about types of normalization?
4. What is the difference between SQL/PL-SQL/embedded SQL?
6. How to store large objects in database. Explain types of LOBS.
7. How to create a user defined datatype?
8. What is Julian date in oracle?
9. What is pseudo column?
10. What is magic table?
11. Name the tables where characteristics of Package, procedure and functions are stored?
12. Please give difference between Truncate, Delete table statements
13. What is global temporary table?
14. Is it possible to fetch next value from a sequence without fetching current value?

Oracle SQL PLSQL Interview questions

1. What is CACHE&NO CACHE in sequences?
2. What is difference between UNIQUE and DISTINCT in select statements?
3. Is it possible to create a primary key without unique index?
4. What command is used to create a table by copying the structure of another table including constraints?
5. What are different types of constraints in SQL?
6. How to hide a table in SQL? I.e. the table can be only visible to its maker?
7. How to create multiple tables in a single statement?
8. What are v$ tables? Name some of them.
9. What is use of USER_ALL_TABLES?
10. How to find currently running queries in database?
11. How to find the locked objects within database?
12. How to know version of oracle and UNIX used?
13. What is difference between TO_CHAR and TO_DATE functions?
14. How to find all values with ‘_’ character in a column?
15. What is difference between analytical functions RANK and DENS_RANK?
16. What is difference between implicit conversions and explicit conversions?
17. What is difference between CASE & DECODE?
18. What are window functions?
19. Explain use of IN/ANY/ALL
20. Please give examples of Sub query and Co-relater query?
21. What is difference between a Record Type and a Table?
22. What are the advantages of primary key over “Unique + Not Null” constraint column?
23. There is a table, on this table there are constraints, indexes, views, synonyms, triggers. What will happen if the table is dropped?
24. Please explain “returning” clause with examples.
25. What are the set operators? Please explain all of them. What is the difference between union & union all clause?
26. What are joins? Explain types of joins?
27. How to use ‘Having’ Clause? Please explain with examples.