Wednesday, May 20, 2015

How to deinstall Oracle 10g database software

How to deinstall Oracle 10g database software

In oracle 10g, you need to use the oui (oracle universal installer) script supplied in the $ORACLE_HOME/oui/bin folder, as shown below.


# Log in as the oracle 10g user, and set the environment to the ORACLE_HOME you are about remove.
# Check the current ORACLE_HOME
echo $ORACLE_HOME
/u01/oracle/product/10.2.0.4/db

# run oui in silent mode, and point to the correct Oracle 10g home:
cd /u01/oracle/product/10.2.0.4/db/oui/bin
./runInstaller -deinstall -silent REMOVE_HOMES={"/u01/oracle/product/10.2.0.4/db"}


Expected output:
Starting Oracle Universal Installer...

No pre-requisite checks found in oraparam.ini, no system pre-requisite checks will be executed.

Preparing to launch Oracle Universal Installer from /tmp/OraInstall2015-05-20_08-51-59AM. Please wait ...
Oracle Universal Installer, Version 10.2.0.4.0 Production

Copyright (C) 1999, 2008, Oracle. All rights reserved.

Starting deinstall

Deinstall in progress (Wednesday, May 20, 2015 8:52:24 AM CEST)
Configuration assistant "iSQL*Plus Configuration Assistant" succeeded
Configuration assistant "Oracle Database Configuration Assistant" succeeded
Configuration assistant "Oracle Net Configuration Assistant - Deinstall Script" failed
............................................................................................................... 100% Done.

Deinstall successful

End of install phases.(Wednesday, May 20, 2015 8:56:17 AM CEST)
End of deinstallations

Please check '/u01/oracle/oraInventory/logs/silentInstall2015-05-20_08-51-59AM.log' for more details.
To verify the deinstallation, check the oracle inventory, in my case /u01/oracle/oraInventory/ContentsXML/inventory.xml

There should be a row similar to:


Remove the old ORACLE_HOME folder physically from disk:
cd /u01/oracle/product
rm -rf 10.2.0.4

How to deinstall Oracle 11g database software

In oracle 11g, you can use the deinstall script supplied in the $ORACLE_HOME/deinstall folder, as shown below.

In my example, I have two Oracle software installations on the host

  • /u01/oracle/product/11203 <-- not in use, can be removed
  • /u01/oracle/product/11204 <-- in use

    cd /tmp
    # first perform a trial run
    /u01/oracle/product/11203/deinstall/deinstall -checkonly
    # do the actual deinstall
    /u01/oracle/product/11203/deinstall/deinstall

    I have found that when you have a listener running on the host out of a different ORACLE_HOME, the deinstall script will often (but not always) want to deconfigure it, despite the fact that it runs out of a different ORACLE_HOME. So for a brief period, the host may be without a valid listener process. However, this was never a problem , simply change directory to the working /u01/oracle/product/11204/network/admin folder and restart the listener.

    Sometimes (but not always) you may have to manually remove the deinstall folder under the ORACLE_HOME home you just deinstalled.
  • Thursday, May 7, 2015

    How to add a logfile group and a logfile member - syntax

    alter database add logfile group 2
    (
    '/u01/app/oracle/flash_recovery_area/mydb/onlinelog/redo02a.log',
    '/u01/app/oracle/oradata/mydb/onlinelog/redo02b.log'
    ) size 50M;
    

    Remember, if you have just recently dropped the redo log members, they are still present physically on disk.
    If you'd like to reuse the log file member names, and to avoid

    ORA-00301: error in adding log file /u03/oradata/arutvt/redo03.log - file cannot be created,
    

    add the REUSE keyword at the end of the statement:

    alter database add logfile group 3 ('/u03/oradata/mydb/redo03.log') size 1024M REUSE;
    
    To add another member to an already existing group:
    ALTER DATABASE ADD LOGFILE MEMBER '/u03/oradata/mydb/redo03.log' TO GROUP 3;
    
    If the redo log file member is already present on disk, use reuse:
    ALTER DATABASE ADD LOGFILE MEMBER '/u03/oradata/mydb/redo3b.log' REUSE TO GROUP 3;
    

    If you do not specifically say which log group number you want to create, Oracle will take add another group based on the largest log file group number in v$logfile. So if I have 3 groups already, and execute
    alter database add logfile '/rdodata/mydb/redo04.log' size 2048M;
    
    It will create group number 4 for you, even if you do not explicitly say so:
    SYS@cdb>SQL>@redo
    
        GROUP# MEMBER                                                     MB ARC STATUS            SEQUENCE#
    ---------- -------------------------------------------------- ---------- --- ---------------- ----------
             1 /rdodata/mydbredo01.log                              2048 YES INACTIVE                220
             2 /rdodata/mydb/redo02.log                             2048 YES INACTIVE                221
             3 /rdodata/mydb/redo03.log                             2048 NO  CURRENT                 222
             4 /rdodata/mydb/redo04.log                             2048 YES UNUSED                    0
    


    Documentation for Oracle 19c is found here

    Thursday, April 30, 2015

    How to find information about CPUs on a Linux server

    On RHEL-based Linux distributions, cat the file /proc/cpuinfo, and you will find detailed information about the server's CPUs, including model name, cache size and vendor.

    cat /proc/cpuinfo | grep processor
    processor       : 0
    processor       : 1
    processor       : 2
    processor       : 3
    

    Or

     lscpu
    Architecture:          x86_64
    CPU op-mode(s):        32-bit, 64-bit
    Byte Order:            Little Endian
    CPU(s):                4
    On-line CPU(s) list:   0-3
    Thread(s) per core:    1
    Core(s) per socket:    1
    Socket(s):             4
    NUMA node(s):          1
    Vendor ID:             GenuineIntel
    CPU family:            6
    Model:                 58
    Stepping:              0
    CPU MHz:               2800.000
    BogoMIPS:              5600.00
    Hypervisor vendor:     VMware
    Virtualization type:   full
    L1d cache:             32K
    L1i cache:             32K
    L2 cache:              256K
    L3 cache:              25600K
    NUMA node0 CPU(s):     0-3
    

    Wednesday, April 29, 2015

    Friday, April 24, 2015

    How to select rows from a specific partition


    The syntax to use if you want to select directly from a specific partition:

    SELECT row1, row2 ... 
    FROM       my_partitioned_table
    PARTITION (my_partition_name)
    WHERE ....;
    

    From a subpartition:
    SELECT row1, row2 ... 
    FROM       my_partitioned_table
    SUBPARTITION (my_subpartition_name)
    WHERE ....;
    

    With Oracle 11g interval partitioning, the syntax has changed so that you can reference a date range, rather than a partition name, since the auto generated names won't say anything meaningful about their content:

    select row1, row2 ..
    from my_partitioned_table
    PARTITION FOR (to_date('25-FEB-2015','dd-mon-yyyy')); 
    

    Remember that aliases must be specified after the entire FROM-clause, including the PARTITION-part, like this:
    select ee.col1
    from my_partitioned_table
    partition (SYS_P2447) ee
    where ee.col2 = 'string1'
    and ee.col3 like '%string2%'
    order by ee.col1,col2;
    

    If you place the alias immediately after the table name, you'll get the error:
    partition (SYS_P2447)
              *
    ERROR at line 3:
    ORA-00924: missing BY keyword
    
    upon execution.

    Tuesday, April 21, 2015

    What do do when Oracle Universal Installer reports missing package pdksh-5.2.14 oracle

    On RHEL 6, if you encounter situations where the OUI is complaining about the absence of a package pdksh-5.2.14 oracle, do the following:

    1. Change directory to /database/stage/cvu/cv/admin 
    
    2. Backup cvu_config: % cp cvu_config backup_cvu_config
    
    3. Edit cvu_config and change the following line:
    
    CV_ASSUME_DISTID=OEL4
    
    to:
    
    CV_ASSUME_DISTID=OEL6
    
    4. Save the updated cvu_config file
    5. Install the 11.2.0.3 or 11.2.0.4 software using /database/runInstaller
    
    % cd /database
    % ./runInstaller
    

    When installing a 32-bit client like in my case, the OUI will warn that "all requirements have not been met".
    This message can be ignored and you can proceed with the installation.
    Source: MOS document ID 1454982.1