Set - 4

Question 36 :

How will you estimate the space required by a non-clustered tables?

Answer :

Calculate the total header size
Calculate the available dataspace per data block
Calculate the combined column lengths of the average row
Calculate the total average row size.
Calculate the average number rows that can fit in a block
Calculate the number of blocks and bytes required for the table.
After arriving the calculation, add 10 % additional space to calculate the initial extent size for a working table.

Question 37 :

How will you monitor the space allocation ?

Answer :

By querying DBA_SEGMENT table/view.

Question 38 :

What is meant by free extent ?

Answer :

A free extent is a collection of continuous free blocks in tablespace. When a segment is dropped its extents are reallocated and are marked as free.

Question 39 :

What is the use of IGNORE option in IMP command ?

Answer :

A flag to indicate whether the import should ignore errors encounter when issuing CREATE commands.

Question 40 :

What is the use of ANALYSE ( Ver 7) option in EXP command ?

Answer :

A flag to indicate whether statistical information about the exported objects should be written to export dump file.