Posts tagged upgrade
Availability is a highly desirable aspect of Fusion Middleware application. Planned downtime therefore sounds quite silly. However, the introduction of changes to applications has typically been associated with the roll out and redeployment of the application causing disruption of service – through loss of existing conversations and unavailability during the deployment process. Several approaches and mechanisms are available in the Oracle stack that will help substantially reduce the loss of uptime because of changes to applications.
First of all, many types of changes may be implemented through run time configuration, rather than software change requiring redeployment of application artifacts. This approach requires good design of aspects of applications that may require modification and the construction of run time mechanisms for applying and processing such changes. The design time at run time capabilities of several Fusion Middleware products go a long way in supporting this approach.
Additionally, several FMW components support short or even long term co-existence of different versions of applications. This means that existing conversations can complete even when a new More >
Reduce occurrence of ORA-04068 while upgrading PL/SQL packages by moving global variables to Application Context0
This article will argue against the use of (stateful) global PL/SQL variables – as they are both a potential problem for stateless web applications and the availability experienced by end users during database upgrades.
In various database releases, Oracle did a lot of work in supporting online redefinition of database objects, striving to a reduction of the impact of changes both in terms of unavailability (through locks) and invalidation of dependent objects. When a table is redefined online, it is accessible to both queries and DML during much of the redefinition process. The table is locked in the exclusive mode only during a very small window that is independent of the size of the table and complexity of the redefinition, and that is completely transparent to users. Through fine grained dependency tracking, the number of occasions on which dependent objects are rendered invalid is reduced to those situations where it is really justified. In database releases prior to 11g, object dependencies were managed at the object level, so altering an object automatically invalidated all dependent objects. Oracle 11g has more granular dependency management, so only changes that directly More >
OOW 2009: The killer feature of Oracle Database 11gR2 – Edition Based Redefinition (or database object versioning)
Today I presented on what is possibly the hottest story on the Oracle Database 11gR2 release: Edition Based Redefinition (EBR). EBR allows us to add a whole new dimension to the database – the Edition (that complements the existing dimensions of schema and object type). Every database object (well, almost every database object – not tables!) can have different implementations/incarnations/versions in various editions. The object versions are all in the same schema – they only differ in the Edition they are created in.
The Edition Based Redefinition has us create Editions in the database – cross database object spaces where new versions of existing database objects can be created – and others can just be inherited from previous editions. We can construct an Edition in isolation – no one is impacted by us creating new objects and versions of objects; objects can be invalid in that edition and no one will know anything about it. Only once the edition is complete, valid and tested can we make it available to new user sessions to work against. Using a simple alter session set edition statement, sessions can specify which edition they want to run against. That is: after the user has More >
Here a small post that hopefully will help some people in the future that are stuck with the same issues. I am still missing some info, but I discovered the workaround for the following "symptoms".FACT’s
I have a VMware environment in which I can play with Oracle BAM and OEM Grid Control on Windows 2003. My current OEM Grid is 10.2.0.3. Because 10.2.0.4 is already out for a while I decided to upgrade my current 10.2.0.3 release. I checked and verified all prerequisites needed before the upgrade. Because I once upgraded the OEM from 10.2.0.1 to 10.2.0.3; and my initial install at that time was an "out of the box" install, no extra steps needed to be done before I could start with the upgrade to 10.2.0.4.
Now it comes… (more…)