Use USE_DB_RECOVERY_FILE_DEST for self-managing deletion rules of the Archived Log files

When using the Fast Recovery Area for storing archive logs, one probably wants to use this location to make use of the self-managing deletion rules of files.

One of these rules is that files are obsolete under the retention policy are eligible for deletion. When for instance RMAN needs space for backup (without delete obsolete option), Oracle will do a similar ‘delete obsolete’ command to make space in the Fast Recovery Area.

For archived logs to be eligible, one MUST use the USE_DB_RECOVERY_FILE_DEST setting for log_archive_dest_x. If the actual location is used, Oracle does not include archived logs in the self-managing deletion rules of files!!! Continue reading

Public yum package ‘oracle-validated’ problems on 64bit OEL

I was preparing some fresh installed OEL5.5 machines for database software installation, but after running ‘yum install oracle-validated‘, the OUI did not pass the prerequisites on two packages. It seems it did not install unixODBC-devel x86_64 and libaio-devel x86_64.

Their Linux may be unbreakable, but their ‘oracle-validated’ package on the public yum server seemed to be broken. Continue reading

Theoretical problem when WebLogic’s NodeManager is using a start script

Many people will use the WebLogic’s NodeManager to use the start script for starting Managed Servers:

StartScriptEnabled=true

The NodeManager will start the Managed Server using the script and monitor the Managed Server when it fails.

One of the mistakes people can make is creating their own start script and start the Managed Server using ‘nohup &’ within this script: Metalink [ID 984122.1] and [ID 861098.1]. The script will finish and the server keeps running, but the NodeManager thinks the Managed Server has failed… Continue reading

Oracle Database version compatibility and support matrix

— Checked for relevance on Januari 21, 2017

The Oracle Database version compatibility matrix and version support status matrix are almost mandatory when installing or upgrading clients or servers.

For information about patches, go here: Oracle database patches for Linux and Windows (on Metalink).

For announcements of security fixes, go to Critical Patch Updates, Security Alerts and Third Party Bulletin.

Oracle Database client / server version compatibility matrix

Oracle calls this Client / Server Interoperability Support, Note ID 207303.1

Oracle Database version release support status matrix

Oracle calls this the Database Releases Support Status Summary, Note ID 161818.1

You will be redirected to Oracle Support and you must be registered to gain access to the pages. I did not include the matrices, because these change over time.

Oracle Information about Windows 32 / 64 bit database and client versions

Certification Information for Oracle Database on Microsoft Windows x64 (64-bit), Doc ID 1307195.1

Oracle 11g AMM: MEMORY_TARGET, MEMORY_MAX_TARGET and /dev/shm

I knew in Oracle 11g with Automatic Memory Management (AMM), the database was able to give unused memory back to the OS, controlled by MEMORY_TARGET and MEMORY_MAX_TARGET.

This mechanism is present in 11g since day 1 (in 2007), but I never actually played with it.

MEMORY_TARGET and MEMORY_MAX_TARGET

The Oracle documents state the following:

MEMORY_TARGET specifies the Oracle system-wide usable memory.
MEMORY_MAX_TARGET (…) decide on a maximum amount of memory that you would want to allocate to the database for the foreseeable future.

So my guess is, MEMORY_MAX_TARGET (static) is the maximum you can set MEMORY_TARGET (dynamic) to. A couple of days ago, I wanted to experiment a bit with these memory settings.

Continue reading

Oracle Database Undo space explained

In this blog post I will talk about the basic workings of Automatic Undo Management, which can cause ORA-01555 and ORA-30036 issues.

The scope is Automatic Undo Management used in 10g and 11g, but has to be explicitly set for 9i (UNDO_MANAGEMENT = AUTO). Manual Undo Management is out of scope for this blog.

The Undo tablespace is a normal tablespace like any other, but only Oracle is controlling what is happening inside it.

Undo something

The Undo tablespace is used for several features: ROLLBACK, READ CONSISTENCY and FLASHBACK technology. Continue reading

Access to HTTPS via utl_http using the orapki wallet command

This HTTPS via utl_http using orapki recipe is prepared with certificates and the orapki tool having some sweet and spicy taste. You may also use the Oracle Wallet manager instead of using orapki but for Oracle RDBMS you will need to have Enterprise Edition and Advanced Security pack licenses. Continue reading

Install Oracle Instant Client / ODAC

Installing the Oracle Instant Client will save you ~600 megabyes compared to the ‘full’ Oracle Client.

Installation steps:

  1. Download Basic Package from the Oracle site
  2. Unzip to directory x (your ORACLE_HOME)
  3. Set PATH (Windows) or LD_LIBRARY_PATH (*nix) to the Instant Client directory x
  4. Move TNSNAMES.ora to directory x/network/admin (or set TNS_ADMIN and ORACLE_HOME).
  5. Extend with SQL*Plus Package (optional)
  6. Start your application

Read my full article here: Whiteblog – Installing the Oracle Instant Client. (links in referred blog might not work!)

ODAC

OLE DB, .NET and ASP.NET drivers are not included in the instant client (first Oracle link might suggest it is). These are included in the ODAC package, download them separately at these locations:

Instant Client vs Full Client (Administrator and Runtime)

What Are The Different Oracle Client Components Installed With Different Installation Types (too much to sum up):

Client master note

Master Note For Oracle Database Client Installation (Doc ID 1157463.1)

Happy consulting!

Checked for relevance on November 4th, 2019.