Wednesday, May 21, 2025

Multiple ways to connect with rman - Oracle database

Multiple ways to connect with rman to oracle database 


1->

[oracle@orcl dbs]$

[oracle@orcl dbs]$

[oracle@orcl dbs]$ rman target "' / as sysdba'"


Recovery Manager: Release 19.0.0.0.0 - Production on Wed May 21 11:38:04 2025

Version 19.3.0.0.0


Copyright (c) 1982, 2019, Oracle and/or its affiliates.  All rights reserved.


connected to target database: DB1 (DBID=1788905834)


RMAN>


2->


[oracle@orcl dbs]$

[oracle@orcl dbs]$

[oracle@orcl dbs]$ rman target /


Recovery Manager: Release 19.0.0.0.0 - Production on Wed May 21 11:38:26 2025

Version 19.3.0.0.0


Copyright (c) 1982, 2019, Oracle and/or its affiliates.  All rights reserved.


connected to target database: DB1 (DBID=1788905834)


RMAN>



3->


[oracle@orcl dbs]$

[oracle@orcl dbs]$

[oracle@orcl dbs]$ rman target /


Recovery Manager: Release 19.0.0.0.0 - Production on Wed May 21 11:38:26 2025

Version 19.3.0.0.0


Copyright (c) 1982, 2019, Oracle and/or its affiliates.  All rights reserved.


connected to target database: DB1 (DBID=1788905834)


RMAN>



4->


[oracle@orcl dbs]$

[oracle@orcl dbs]$

[oracle@orcl dbs]$ rman target sys/sys


Recovery Manager: Release 19.0.0.0.0 - Production on Wed May 21 11:42:47 2025

Version 19.3.0.0.0


Copyright (c) 1982, 2019, Oracle and/or its affiliates.  All rights reserved.


connected to target database: DB1 (DBID=1788905834)


RMAN>


RMAN>


How to configure the size of Fast Recovery Area (FRA) in Oracle database ?

Configure the size of FRA 

 


SQL>

SQL>

SQL> show parameter db_recovery


NAME                                 TYPE        VALUE

------------------------------------ ----------- ------------------------------

db_recovery_file_dest                string      /u01/app/oracle/fast_recovery_

                                                 area

db_recovery_file_dest_size           big integer 12732M

SQL>

SQL>

SQL> alter system set db_recovery_file_dest_size=12G scope=both ;


System altered.


SQL> show parameter db_recovery_file_dest_size;


NAME                                 TYPE        VALUE

------------------------------------ ----------- ------------------------------

db_recovery_file_dest_size           big integer 12G

SQL>

How to add a redo log member to an existing redo log group in an Oracle database | Redo log files Multiplexed

Add a redo log member to an existing redo log group in an Oracle database


SQL> select group#,status,member from v$logfile;


    GROUP# STATUS

---------- -------

MEMBER

--------------------------------------------------------------------------------

         3

/u01/app/oracle/oradata/DB1/redo03.log


         2

/u01/app/oracle/oradata/DB1/redo02.log


         1

/u01/app/oracle/oradata/DB1/redo01.log



SQL>

SQL> select group#,members,archived,status from v$log;


    GROUP#    MEMBERS ARC STATUS

---------- ---------- --- ----------------

         1          1 NO  CURRENT

         2          1 YES INACTIVE

         3          1 YES INACTIVE


SQL>

SQL> alter database add logfile member '/u01/app/oracle/oradata/DB1/redo01b.log' to group 1;


Database altered.


SQL> select member from v$logfile;


MEMBER

--------------------------------------------------------------------------------

/u01/app/oracle/oradata/DB1/redo03.log

/u01/app/oracle/oradata/DB1/redo02.log

/u01/app/oracle/oradata/DB1/redo01.log

/u01/app/oracle/oradata/DB1/redo01b.log





SQL> 



Best Practices & Notes


Always add members on different disks for redundancy.

The new log file must not exist already on disk.

All members of a group are written to simultaneously — they are identical.

Adding a member does not affect the database availability.

Thursday, May 15, 2025

Two key features of Oracle Exadata Machine

Smart Scan (Exadata Smart Storage):


Offloads query processing to the storage layer, reducing the amount of data sent to the database servers.

Enables operations like filtering, column projection, and join processing to be performed directly on the storage servers, improving query performance significantly.


Hybrid Columnar Compression (HCC):


Provides advanced data compression techniques to reduce storage requirements and improve I/O performance.

Optimized for both OLTP (Online Transaction Processing) and OLAP (Online Analytical Processing) workloads, enabling faster query execution and efficient storage utilization.