Set - 4

Question 26 :

What is the use of COMPRESS option in EXP command ?

Answer :

Flag to indicate whether export should compress fragmented segments into single extents.

Question 27 :

How will you swap objects into a different table space for an existing database ?

Answer :

Export the user
Perform import using the command imp system/manager file=export.dmp indexfile=newrite.sql.
This will create all definitions into newfile.sql. Drop necessary objects.
Run the script newfile.sql after altering the tablespaces.
Import from the backup for the necessary objects.

Question 28 :

How does Space allocation table place within a block ?

Answer :

Each block contains entries as follows
Fixed block header
Variable block header
Row Header,row date (multiple rows may exists)
PCTEREE (% of free space for row updation in future)

Question 29 :

What are the factors causing the reparsing of SQL statements in SGA?

Answer :

Due to insufficient Shared SQL pool size. Monitor the ratio of the reloads takes place while executing SQL statements. If the ratio is greater than 1 then increase the SHARED_POOL_SIZE. LOGICAL & PHYSICAL ARCHITECTURE OF DATABASE.

Question 30 :

What is dictionary cache ?

Answer :

Dictionary cache is information about the databse objects stored in a data dictionary table.