- Source: Metadata publishing
Metadata publishing is the process of making metadata data elements available to external users, both people and machines using a formal review process and a commitment to change control processes.
Metadata publishing is the foundation upon which advanced distributed computing functions are being built. But like building foundations, care must be taken in metadata publishing systems to ensure the structural integrity of the systems built on top of them.
Definition of metadata publishing
Published metadata has the following characteristics:
Metadata structures available to the general public on a public web site or by a download
There is a documented review and approval process for adding or updating data elements to the system
New releases are made available without disturbing prior versions
A publishing organization that makes a commitment to change control process
Benefits of metadata publishing
When classifying benefits of metadata publishing two groups are usually considered. External parties are usually consumers of information that are not part of the publishing organization. Internal parties are usually the various business units or departments within an organization.
= Benefits to external parties
=Allows external systems (both people and agents) to have a clear understanding of the semantics of data elements in a system
Allows third parties to build semantic maps between data models and import and export data between systems
Promotes service oriented architectures and allow horizontal sharing of information between traditional information silos
Allows systems to participate in accurately indexed and federated search processes
= Benefits to internal parties
=allows parties from diverse business units to agree on shared data definitions and separate department or function specific definitions
makes Extract, transform, load (ETL) operations more precise for data warehousing
allows user interface designers to access a common pool of screen and report header labels
promotion of model-driven architecture
Objections to metadata publishing
Organizations that publish their metadata could make it easier for unauthorized people to find sensitive data if they breach an organization's firewall
Vendors that publish their metadata risk customers creating tools that could allow their customers to export their data from computer systems, therefore making it easier to migrate off of a vendor's system
Core process in metadata publishing
The following are some of the core processes in metadata publishing
Gathering of metadata requirements
Selection of metadata registry and metadata publishing tools
Training of metadata concepts to project participants
Stakeholder group formation
Metadata harvesting
Glossary consolidation
Initial upper ontology construction (abstract data elements)
Draft data element loading
Data element review process
Publishing approved metadata elements in a variety of output formats (see below)
Creation and maintenance of versions and depreciation of unused or redundant data elements
File format metadata publishing
Organizations that create applications that store data in file systems can also publish metadata definitions. One common way to perform this is to store application data in a compressed XML file format. The XML files can be uncompressed and validated against an external XML Schema. An example of this is done by the Open Source FreeMind tool.
Metadata publishing formats
HTML - used for browsing a web site and indexing by text-based search engines
Web Ontology Language (OWL) - used by metadata search engines such as Swoogle
XML Metadata Interchange (XMI) - OMG standard for exchanging metadata
Common Warehouse Metamodel (CMW) - OMG standard for data warehouse metadata
Topic maps - an ISO standard for the representation and interchange of knowledge, with an emphasis on the findability of information.
KM3 or Kernel Meta Meta Model as used in the Metamodel Zoos. The AtlanticZoo is an open source library of more than 100 metamodels under EPL License. KM3 is a simple Domain Specific Language for specifying metamodels. A number of transformations are available to translate from KM3 to other notations like XMI.
See also
Bibliographic database
Data governance
metadata
Semantic web
Semantic technology
Metadata registry
ISO/IEC 11179
Topic Maps
External links
MetaQuery examples Archived 2007-10-28 at the Wayback Machine provided by Ambient Webs LLC
SWED portal provided by WordPressHelp
Microsoft Metadata Publishing Example