The dynamic replication of data via materialized
views is shown in Figure 17-4.
You can use Data Guard to create and manage a standby database whose content is updated
whenever the primary database??™s data changes. The standby database can be used as a read-only
database to support reporting requirements and then returned to its status as a standby database.
See Chapter 13 for details on the use and management of standby databases.
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604 Oracle Database 11g DBA Handbook
Managing Distributed Data
Before you can worry about managing transactions against remote databases, you have to get the
data there and make it globally accessible to other databases. The following sections describe the
requisite management tasks: enforcing location transparency and managing the database links,
triggers, and materialized views.
NOTE
The examples in this chapter assume that you are using tnsnames.ora
files for your database service name resolution.
The Infrastructure: Enforcing Location Transparency
To properly design your distributed databases for long-term use, you must start by making the
physical location of the data transparent to the application. The name of a table within a database
is unique within the schema that owns it. However, a remote database may have an account with
the same name, which may own a table with the same name.
Within distributed databases, two additional layers of object identification must be added.
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