"The Meta Data Coalition (MDC) Open Information Model (OIM) is a vendor-neutral and technology-independent specification of core metadata types found in operational, data warehousing, and knowledge management environments. The Extensible Markup Language (XML) is the standard format for the interchange of metadata using the MDC OIM. XML at its core is a definition language that allows specifying how information may be represented by tagged structures that can be nested and attributed."
"XML, however, does not define how models such as the MDC OIM are mapped onto tags or structures, known as XML vocabulary. Multiple technology dependent and vendor-specific mapping technologies have appeared or have been proposed in the market, many are industry standards (BizTalk, EDI, STEP), related to component technologies (COM, CORBA, EJB), or are simply vendor dependent.
"The MDC will support multiple XML vocabularies for the OIM in order to make it easy for different vendors and end-user to integrate the standard into their environments. By standardizing on the MDC OIM as semantic model for a metadata interchange, it is straightforward to convert between different XML vocabularies using technologies like the W3C Extensible Style Sheet Language (XSL), a standard mapping technology. The MDC will use XSL to provide mappings between the alternative XML vocabularies for the MDC OIM."
"The Extensible Markup Language (XML) is the standard format for the interchange of metadata using the MDC OIM. Microsoft and the Coalition posted for review an OIM XML encoding format specification and a set of Document Type Definitions (DTDs) that will make it easier to understand the XML documents and to develop XML-based import/export functionality."
The Open Information Model (OIM) is a set of metadata specifications to facilitate sharing and reuse in the application development and data warehousing domains. OIM is described in UML (Unified Modeling Language) and is organized in easy-to-use and easy-to-extend subject areas. The data model is based on industry standards such as UML, XML, and SQL. It has been reviewed by over 300 companies. The Open Information Model is grouped into subject areas: (1) Analysis and Design Models; (2) Objects and Components Models; (3) Database and Data Warehousing Models; (4) Knowledge Management Models; (5) Business Engineering Models. The OIM is a core model of the most commonly used metadata types. Starting with an abstract core model and adding additional subject areas over time has proven to be the most effective strategy in model development, reducing redundancy and promoting extensibility. By first defining a domain-specific model for a generic subject area that addresses the implementation-neutral aspects of that area, and only later specializing it to one or more specific subject areas that describe the tool-specific extensions, the OIM minimizes redundancy and enables application neutrality sharing and reuse."
References:
The Open Information Model - Overview
Meta Data Coalition Open Information Model (OIM). Version 1.1 (Proposal) 245 pages. "Meta data is descriptive information about the structure and meaning of data and of the applications and processes that manipulate data. Meta data can be grouped into two categories: technical and business meta data. Technical meta data supports designers, developers, and administrators during development, maintenance, and management of an information technology environment. It is the technical glue that links the tools, applications, and systems that together constitute a solution. For example, technical meta data can address database structures, installed applications, server systems, and so forth. Business meta data, on the other hand, makes the services of the enterprise environment more understandable to end-users. For example, it provides explanations of the business objects and processes to ease browsing, navigation, and querying of data. . . The MDC Open Information Model is a specification of a core set of meta data types such as database schema, business process, or business object elements. The Unified Modeling Language (UML) is the modeling standard for specifying and representing meta data types for the MDC OIM. Based on the formal representation of the meta data specification in the UML, it is possible to generate automatically all the necessary deliverables to deploy implementations of the specifications in tools or repositories. The UML is the most abstract description of information structures by classes arranged into a generalization / specialization hierarchy. The Open Information Model is a specialization of the abstract concepts of UML into domain specific types that describe meta data. It represents an industry agreement on a detailed semantics of types such as a table definition. The instances of the Open Information Model represent the descriptive information about enterprise data such as actual SQL Schema, OLAP Schema, or business process definitions. The meta data types -- along with their attendant native interchange format and relational query schema -- form a comprehensive, easy-to-use, and standards-based solution for the integration of meta data in an enterprise environment, including the extension and customization of the meta data model itself. The use of standard definitions enables linking of heterogeneous implementations. The following standard technologies are used to provide implementations of the MDC OIM: (1) The Unified Modeling Language (UML) as the formal specification language for OIM, (2) The eXtensible Markup Language (XML) as the interchange format for OIM, and (3) The Structured Query Language (SQL) as the query language for OIM." [cache]
Meta Data Coalition Open Information Model. XML Encoding, Version 1.0., Review Draft. September 1999. 23 pages. APPENDIX A: Sample XML Encoding; APPENDIX B: EBNF Representation; APPENDIX C: Namespaces in the OIM; APPENDIX D: DTD for the OIM Namespace. "This document describes a set of rules that govern the encoding of metadata objects described by OIM in XML. The XML encoding of OIM types enables the interchange of metadata between heterogeneous repositories. It is also a wire-encoding format to use between repositories and tools. The encoding format defined in this specification is completely driven by the abstract model. As the names of the element and attribute tags used in the representation are derived from the model, documents can be generated and parsed automatically by any implementation of OIM, regardless of technology. Accompanying this specification is a set of XML Document Type Definitions (DTDs), which together form a grammar to express the structure of XML instances. DTDs are currently the only approved mechanism to describe the structure of XML documents. In its current form, DTD is not expressive enough to completely cover the semantics of OIM. A correct interpretation of an XML document is therefore only possible based on the OIM specification. However, DTDs have been supplied to make understanding of the XML documents easier and to help with the development of XML import/export functionality based on this encoding format." PDF Format. [local archive copy]
OIM XML DTDs. The DTDs for review as of 1999-10-04 cover: Unified Modeling Language (UML), UML Extensions, Common Data Types, Generic Elements, Component Description Model, Database Schema Elements, Data Transformation Elements, OLAP Schema Elements, Record Oriented Legacy Databases, Semantic Definition Elements.
"Open Information Model Proposed XML Document Type Definitions: Accompanying the encoding specification is a set of XML Document Type Definitions (DTDs), which together form a grammar to express the structure of XML instances. DTDs are currently the only approved mechanism to describe the structure of XML documents. In its current form, DTD syntax is not expressive enough to completely cover the semantics of OIM. A correct interpretation of an XML document is therefore only possible based on the OIM specification. However, DTDs have been supplied to make understanding of the XML documents easier and to help with the development of XML import/export functionality based on this encoding format. You can view a quick reference guide to understanding the DTD format. DTDs: "The DTDs are divided into two sections, with the top section describing all concrete classes in the information model and the bottom section describing the associations between these classes. The class declaration includes the set of related associations and a list of attributes for the class. Note that while every attribute for a class is listed, only associations in the same information model are listed. Associations that the class inherits from a superclass are handled using the ANY token. DTDs do not have a mechanism for describing element specialization so the inheritance for a class is described in the comment header..." cache DTDs
[September 25, 2000] "Competing Data Warehousing Standards to Merge in the OMG." - "Today, the Meta Data Coalition (MDC) and the Object Management Group (OMG), two industry organizations with competing data warehousing standards, jointly announced that the MDC will merge into the OMG. As a result, the MDC will discontinue independent operations and work will continue in the OMG to integrate the two standards. Until this week, there were two major standards for metadata and modeling in the areas of data warehousing and component-based development. Data warehousing is a response to the enterprise need to integrate valuable data spread across organizations from multiple sources. Analysis of an enterprise's accumulated data not only allows sales and production to be tuned for maximum profitability, but also allows entirely new and profitable products to be discovered and exploited. However, it is difficult to merge data into a single warehouse when its sources are spread over a number of different databases, using different data models. The merger of MDC into the OMG marks an agreement of the major data warehousing and metadata vendors to converge on one standard, incorporating the best of the MDC's Open Information Model (OIM) with the best of the OMG's Common Warehouse Metamodel (CWM). When the work is complete, the resulting specification will be issued by the OMG as the next version of the CWM. A single standard will allow users to exchange metadata between different products from different vendors freely. . . Founded in 1995, the Meta Data Coalition (MDC) is a not-for-profit consortium of 50 vendors and end-users, including BMC, Informatica, CA, NCR, Microsoft, and SAS, whose goal is to provide a tactical solution for metadata exchange. The Coalition developed the MDC OIM (Open Information Model), a technology-neutral and vendor-independent metadata standard that is comprised of the Meta Data Interchange Specification (MDIS) and the OIM, originally submitted by Microsoft. Since the MDC OIM 1.0 became available in July 1999, work has been under way to align the standard with the CWM developed by OMG. On August 31, MDC membership voted to formalize the decision to merge with OMG. The Object Management Group's Common Warehouse Metamodel builds on various standards, including OMG's UML (Unified Modeling Language), XMI (XML Metadata Interchange) and MOF (Meta Object Facility), and on the Coalition's OIM. The CWM was developed by a number of companies, including IBM, Oracle, Unisys, Hyperion, Genesis, NCR, UBS, and Dimension EDI, and is an adopted OMG standard." See "MDC Open Information Model (OIM)" and "OMG Common Warehouse Metadata Interchange (CWMI) Specification."
[April 20, 1999] "Meta Data Coalition accepts the Open Information Model as a standard, work underway on extensions." - "The Meta Data Coalition (MDC) announced today the acceptance of the MDC Open Information Model (OIM) as a standard. The MDC OIM is a technology-independent and vendor neutral metadata standard that is based on technology developed by Microsoft Corp. together with over 20 leading industry partners. Microsoft transferred the right to maintain and evolve the OIM, a product that ships in SQL Server 7.0 and Visual Studio 6.0, to the MDC at the end of 1998. The technical work by the MDC has concluded with a vote by the membership on July 15th to adopt this as a standard."
[April 20, 1999] "Meta Data Coalition and Object Management Group form cooperative relationship to build consensus on metadata standards." - "The Meta Data Coalition (MDC) and the Object Management Group (OMG) announced today their first cooperative effort to develop metadata standards. In establishing a formal technical liaison, the MDC is now a Platform Member of the OMG, and the OMG is a member of the MDC."
[November 08, 1999] "Meta Data Coalition Drives New Key Initiatives. November 11 Technical Meeting, Open to All Coalition Members, Will Address These Initiatives Plus Several New Models." - "The Meta Data Coalition (MDC), a not-for-profit organization in the process of standardizing metadata, announced today several new key initiatives as part of its technical meeting November 11, 1999. In July 1999, the membership of the Meta Data Coalition ratified the MDC-OIM 1.0, which provides the basic meta-model for representing databases and the interrelationships between them. The new initiatives will extend the model into several key areas such as business models and information portals. This will enable the integration of an even larger set of tools and business applications using the MDC-OIM and its XML interchange format. MDC and OMG Aligning Metadata Standards in the Market: As a result of the Metadata Coalition's membership exchange with the Object Management Group (OMG), the data warehousing part of the MDC-OIM has been used as a design reference for the OMG's CWMI (Common Warehouse Metadata Interchange). With the continued co-operation between the technical task forces of both organizations, the metadata standards will be aligned. The MDC has established a collaboration with the European Commission's ESPRIT Project ATLAS, which is headed by Unisoft, Greece. ATLAS incorporates technologies for real-time business information systems and plans to use the MDC-OIM Business Engineering and Knowledge Management Models to drive the transition from online to real-time business information systems... Standardized Metadata for Component (Object) Design and Reuse [is] a component model [which] specifies component interfaces and describes the design, assembly and deployment of components into a system, based on some standard component architectural style. The new model provides the necessary metadata types for these descriptions. The work is based on the meta-model of Catalysis, a UML-based methodology for end-to-end component-based development."
