1. NORMALIZATION? WHAT IS THE USE OF NORMALIZATION?
2. SUBQUERIES AND TYPES IN SUBQUERIES?
3. EXPLAIN INLINE QUERY OR SCALAR QUERY?
4. EXPLAIN DUAL TABLE?
5. WHAT WILL HAPPEN IF SCALAR SUBQUERIES EXECUTES?
6. WHAT WILL HAPPEN IF USE '-' IN REPLACE(THIRUNA,' ',-) ?
7. EXPLAIN HIERARCHICAL STRUCUTRE? TELL ABOUT CONNECT BY PRIOR?
8. IF CONSTRAINTS ERROR IN MAIN TABLE DID TRIGGER WILL UPDATE IF WE USED AFTER UPDATE? 
   TELL ME HOW AND WHY IT WILL NOT UPDATE?
9. WHAT IS YOUR CHOICE IF YOU UPDATE 2GB OF DATA IN TABLE FOR PERFORMANCE?
10. IN PROCEDURE PARAMETER WHAT IS THE USE 'NO COPY DATA'?
11. EXPLAIN BULK COLLECT?
12. EXPLAIN HINTS? NO INDEX,APPEND,PARALLEL HINTS?
13. WHAT IS THE USE OF INDEX?
14. HOW INDEX WILL WORK IN BACKEND?
15. WHAT YOU DO IF SELECT QUERY TAKES 2 TO 4 HOURS OF RUNNING? IF THE SAME QUERY RUNS FOR 2 MINUTES?
16. EXPLAIN PARTITION? WHEN YOU CREATE PARTITION? AND HOW IT WILL WORKS ?