PL/SQL Interview Question and Answers

9. What is cascading invalidation?
 
  • Suppose objects A references object B, which in turn references object C, then A is an indirect dependent of object C.
  • If object C is changed, then object B is invalidated; and therefore, invalidates object a as well.
  • This is called cascading validation.
10. What is the usage of DBMS_LOB package?
  The DBMS_LOB package helps PL/SQL programs to access and manipulate the LOB objects.
11. What are temporary LOBs?
 
  • Temporary LOBs are like local variables to store datatypes.
  • They can be of CLOBs, BLOBs, or NCLOBs type.
  • The data for temporary LOBS is stored in the temporary table space and not in tables.
  • They are available only within a user session and deleted at the end of the session.
12. Is it possible to convert CLOB to CHAR type?
  Yes, It is possible to convert CLOB to CHAR type using the TO_CHAR function.
Page 3 of 10 12 345678910