Database Reference
In-Depth Information
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Federation members
: hey are the partitions of a federation. Each federation member
will be implemented on an SQL database, which is physically separated from other SQL
databases.
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Federation atomic unit
: It is a set of related database objects such as tables stored in one
federation member. A federation atomic unit is labeled with a speciic federation key value.
he database objects in an atomic unit are bound together by the federation key assigned to
the atomic unit.
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Federated table
: It is a table with its partitions distributed across multiple federation
members.
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Reference table
: It is a table with no partitioned rows. It contains reference information and
is used for lookup purposes.
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Federation root
: It is the database that contains federations and federation directory.
Federation members can be accessed through the federation root. As a federation root, the
database may also contain global data such as users, passwords, roles, or other application-
speciic data.
Partition members are physically separated. Each of the partition members is implemented as a
database named with a federation key. As an example, Figure 8.28 illustrates the federations built
in a federation root.
Windows Azure SQL Database provides an ideal environment for implementing the federa-
tions. In the SQL Database environment, the physical IT infrastructure is highly scalable. If
needed, federation members can be built across hundreds or even thousands of databases. SQL
Database manages the physical IT infrastructure, which hosts those databases. Without spending
time on physical infrastructure management, database administrators and application develop-
ers are able to focus on the development of federations over the logical databases. he Windows
Azure Management Portal can be used for federation deployment and management. Also, a fed-
eration built in SQL Database is highly available. It can be accessed anywhere and anytime. SQL
Database provides the 99.9% service-level agreement (SLA) to ensure high availability. It also
helps with rebalancing of a federation by adding or removing federation members based on the
workload.
Figure 8.28
Federation architecture.
