Tuesday, December 15, 2009

How To Run Dbv In Parallel On A Single data file.

To run dbv in parallel on a single datafile. Steps -----
1) Identify the file# and name of the datafile.
2) Identify the number of blocks in the datafile.

3) Determine how many parallel sessions has to be used.
4) Start Parallel dbv sessions.

1) I dentify the file# and name of the datafile.
select * from v$dbfile where name like '%datafile_name%'; (OR) select * from v$dbfile ;
2) Identify the number of blocks in the datafile.

1.A Find Data Block Size
eg: SQL>show parameter db_block_size
NAME TYPE VALUE
----------------------------------- ------- ------
db_block_size integer 8192
1.B Calculate the the number of blocks.
SQL> select BYTES/8192 from v$datafile where FILE#=5;
BYTES/8192
----------
5120
So the file# 5 contains 5120 blocks

3) Determine how many parallel sessions has to be used.
This example shows three parallel sessions.
4) Start Parallel dbv sessions.
$dbv FILE=filename START=1 END=2000
$dbv FILE=filename START=2001 END=3500 $dbv FILE=filename START=3501 (Note:-END defaults to the last block of the file)

1 comment:

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