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IO calibrate statistics are missing in oracle explain plan

IO calibrate statistics are missing  in explain plan, then below mentioned steps should be executed one by one :-

set these parameters

1.alter system set filesystemio_options=asynch scope=spfile
2.alter system set disk_asynch_io = true scope=spfile;
3.bounce the db
4.Ensure asynchronous I/O is enabled on all datafiles and tempfiles. The following query can be used to            verify asynchronous I/O for these files.

col name format a50
select name,asynch_io from v$datafile f,v$iostat_file i
where f.file#=i.file_no
and (filetype_name='Data File' or filetype_name='Temp File');
/

5.run the calibration procedure :-

SET SERVEROUTPUT ON
DECLARE
  l_max_iops        PLS_INTEGER;
  l_max_mbps        PLS_INTEGER;
  l_actual_latency  PLS_INTEGER;
BEGIN
  DBMS_RESOURCE_MANAGER.calibrate_io (
    num_physical_disks => 1,
    max_latency        => 20,
    max_iops           => l_max_iops,
    max_mbps           => l_max_mbps,
    actual_latency     => l_actual_late…

change oracle database name using nid

First of all start your database in mount state . Here I am changing the database name from orcl to orcl4. Then perform below steps :-

[oracle@host01 dbs]$ sqlplus sys/sys as sysdba

SQL*Plus: Release 11.2.0.1.0 Production on Fri Mar 7 12:09:36 2014

Copyright (c) 1982, 2009, Oracle.  All rights reserved.


Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options

SQL> select open_mode from v$database;

OPEN_MODE
--------------------
MOUNTED

SQL> exit
Disconnected from Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options

[oracle@host01 dbs]$ nid target=sys/sys DBNAME=orcl4

DBNEWID: Release 11.2.0.1.0 - Production on Fri Mar 7 12:14:08 2014

Copyright (c) 1982, 2009, Oracle and/or its affiliates.  All rights reserved.

Connected to database ORCL (DBID=1305795399)

Connected to server versi…

Things to consider before moving table

The following thing can be potential problem for big size table move .

1. No transaction should access those tables which you are going to move otherwise there will be ORA error on application side .So better to use dbms_redifnation in this case.( dbms_redifnation is available only EE edition) .

2. Time estimation can be go wrong .It may be due to different storage type used ( some times in some scenario the moving table reside on attached hard disk level file system and target reside on NAS or SAN ). I have seen that even 100GB of table takes time around 4 hours although target tablesapce and source tablespace were on different mount point but on same storage ( it was SAN ) .

3. Always use DBverify command to check block level corruption on target datafile before moving large tables .Otherwise it stuck in the middle of operation and some times it gets failed .

4.you can not use index rebuild on BITMAP index on partition table , if it is invalid state , you have to drop and rebuild …

configuring archive and backup

1.Log on the target server and find out database is in archive log or not :-

Export ORACLE_SID=<database_name>
Sqlplus / as sysdba
SQL> archive log list;
Database log mode              No Archive Mode
Automatic archival             Disabled

2.Create respective directories for backup in the name of database on the backup location and grant permission on it .

mkdir –P /backup/$ORACLE_SID/flash_recovery_area

chmod –R 777 /backup/$ORACLE_SID/flash_recovery_area

chown –R oracle:oinstall /backup/$ORACLE_SID/flash_recovery_area


3.Configure database in archive log, recovery area ,recovery location  :-

SQL>create pfile from spfile;
(take backup of pfile)

SQL> select * from v$recovery_file;
(Here none of the datafile should be there)

SQL> show parameter recovery_file_dest;

SQL> alter system set log_archive_dest_1='LOCATION=/backup/$ORACLE_SID/flash_recovery_area' scope = both;

SQL> alter system set db_recovery_file_dest_size=(db_size+archivelog+20%);

SQL>shut…