|
Enterprises have to coordinate the business
processes across their departments and their business partners
and customers. These business processes or applications were
developed to cater to the specialized needs of the individual
departments. Hence, these applications have different data
models. To coordinate these business processes, message transformation
of the communications of these departments is necessary.
Advanced Queuing (AQ) is the database integrated
message queuing feature designed to meet the needs of coordination
of the internal and external business processes of an enterprise.
Its offers message transformation feature which can be used
to transform and validate message communication amongst different
business processes. The message transformations are defined
as user defined SQL expressions which can involve PL/SQL,
Java, or C implemented functions. These mappings allow the
use of the transformations defined by transformation vendors
such as Mercator. These defined transformation mappings can
be used at various points of advanced queuing operations such
as message production (enqueue), message consumption (dequeue),
or message distribution (propagation).
Using message transformation feature of Advanced
Queuing is a two step process:
- Defining Transformation Mapping
- Using the defined Transformation Mapping
in an AQ operation
Defining
Transformation Mapping
DBMS_TRANSFORM package
has the various functions that are used to define the transformation
mapping. Some of the useful functions are CREATE_TRANSFORMATION,
MODIFY_TRANSFORMATION, and DROP_TRANSFORMATION.
Using
the Defined Transformation Mapping
The transformation mappings can be used during
AQ operations - enqueue, dequeue, and propagation. To use
the transformation mapping at enqueue, the transformation
mapping has to be specified in enqueue_options during
an enqueue call. To use the transformation mapping at dequeue,
the mapping can be specified either at add_subscriber
or in dequeue_options during a dequeue call. If the
mapping is specified at both dequeue_options and add_subscriber,
the one specified at dequeue_options overrides the
add_subscriber one. In order to use the transformation
mapping at propagation, the transformation mapping has to
be specified at add_subscriber call.
More
Info
 Advanced
Queuing
Oracle9i
Database Daily Features
|
Bookmark
