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Oracle Grid & Real Application Clusters. To get immediate
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Many enterprises are showing
keen interest in data or database consolidation. For example, dozens
of instances residing on several hosts or servers are merged into a
large database. With a powerful server platform, abundant memory,
and ample processor resources, it is common to establish a very
large database (VLDB) that can accumulate terabytes of data.
Even in a packaged application
environment, as in SAP, there is a tendency towards consolidating
the databases to provide lower cost and better administrative
flexibility. A good example is the new approach taken by the
SAP application suite that is called Multiple Components in One
MCOD is a new installation
feature for mySAP.com components. It provides the capability of
installing several components independently in one single database.
Each mySAP.com component connects the database with one single
Oracle VLDB has proven to be a
good cost saving solution. It employs dynamic parallel processing
techniques in accessing data sets and table partitions. Even from
the administrative point of view, it makes more sense for management
to have a smaller number of large databases than vice versa. This
* Reduced TCO in terms of
licensing, staffing, and consulting fees.
* Improved availability with the
focus on fewer databases.
* Higher security.
* Centralized backup and
RAC with Grid is an ideal
solution to take advantage of these developments. RAC supports VLDB
databases for data consolidation and large data warehousing
E-business applications are
becoming a dominant category considering the steep growth of the use
of Internet in commercial, retail, and entertainment businesses.
E-business activity brought many challenging demands to IT
management. The wide adoption of e-business as a way of commerce by
the common public has resulted in a huge accumulation of data at
these enterprises. Supporting these applications 24/7 has become the
most important feature. It is common for thousands of concurrent
users to access an e-business application and the associated
As a result, the workload
pattern has become almost unpredictable. There may be sudden spurts
of commerce activity at any time. The days are gone when database
systems were shutdown during the night and weekends for backups and
other maintenance activities.
RAC databases, with the built-in
multiple instance nodes and pay as you grow approach, are a good
solution for meeting all these challenging developments.
The next section will cover the
suitability of RAC databases for application deployment.
In a typical 2-tier or 3-tier
application deployment, the back end tier consists of the database
component, with the middle tier accessing the backend database
resources. There are hardly any applications that do not depend on
database resources. Whether it is a web-based e-commerce
application, or an in-house client server application, or packaged
applications like ERM and CRM, they all need database resources to
store, retrieve, and update.
The Oracle RAC GRID enabled
database is a very well positioned back end database that provides a
scalable and highly available data storage platform. With its
increased robustness and higher computing power, it provides a
reliable back end database engine for mission critical applications
needing higher throughput and shorter response times.
Multi-instances and multiple nodes make it an enhanced and powerful
database platform. Most applications can use this multi-node
clustered database without any code modification. As a result, the
acceptability of multi-instance RAC databases is very high among
existing and stand-alone Oracle database users.