The Common Warehouse metamodel (CWM™) specifies interfaces that can be used to enable easy interchange of warehouse and business intelligence metadata between warehouse tools, warehouse platforms and warehouse metadata repositories in distributed heterogeneous environments.
CWM is based on
three standards:
UML - Unified Modeling Language, an OMG modeling standard
MOF - Meta Object Facility, an OMG metamodeling and metadata
repository standard
XMI - XML Metadata Interchange, an OMG metadata interchange standard
The UML standard defines an object-oriented modeling language that is supported
by a range of graphical design tools. The MOF standard defines an extensible framework for defining models for metadata, and providing tools with programmatic
interfaces to store and access metadata in a repository. The XMI standard allows
metadata to be interchanged as streams or files with a standard format based on XML.
The complete architecture offers a wide range of implementation choices to developers
of tools, repositories and object frameworks. XMI in particular lowers the barrier to
entry for the use of OMG metadata standards.
These three standards form the core of the OMG metadata repository architecture as
illustrated in the following figure.
Key aspects of the architecture include:
A four layered metamodeling architecture for general purpose manipulation of
metadata in distributed object repositories. See the MOF,
UML, and XMI
specifications
for more details
The use of UML notation for representing metamodels and models
The use of standard information models (UML) to describe the semantics of object
analysis and design models
The use of MOF to define and manipulate metamodels programmatically using fine
grained CORBA interfaces. This approach leverages the strength of CORBA distributed object infrastructure.
The use of XMI for stream based interchange of metadata
This specification mainly consists of definitions of metamodels in the following
domains:
Common Warehouse Metamodel: An Introduction to the Standard for Data Warehouse Integration by John Poole, Dan Chang, Douglas Tolbert, David Mellor Average Customer Review: based on 7 reviews. Customer Review: By far, the finest presentation of a new (to me) concept I have seen in a long time. Structure of book is ideal, with a strong writing style, fantastic use of graphics, and examples that aid in understanding. I knew virtually nothing about CWM before reading this book -- I know a good deal now. Excellent, understandable writing style...
based on 7 reviews.
