《ANSI-ISO-IEC-11179-4-1995.pdf》由会员分享，可在线阅读，更多相关《ANSI-ISO-IEC-11179-4-1995.pdf（18页珍藏版）》请在三一文库上搜索。
1、I N T E R NAT I O NA L STANDARD ISOJIEC 11179-4 First edition 1995-07-01 Information technology - Specification and standardization of data elements - Part 4: Rules and guidelines for the formulation of data definitions Technologies de linformation - Spcification et normalisation des donnes - Partie
2、 4: Rgles et directives pour la formulation des dfinitions des donnes Adopted by INCITS (InterNational Committee for Information Technology Standards) as an American National Standard. Date of ANSI Approval: 1/11/99 Published by American National Standards Institute, 25 West 43rd Street, New York, N
3、ew York 10036 Copyright 2002 by Information Technology Industry Council (ITI). All rights reserved. These materials are subject to copyright claims of International Standardization Organization (ISO), International Electrotechnical Commission (IEC), American National Standards Institute (ANSI), and
4、Information Technology Industry Council (ITI). Not for resale. No part of this publication may be reproduced in any form, including an electronic retrieval system, without the prior written permission of ITI. All requests pertaining to this standard should be submitted to ITI, 1250 Eye Street NW, Wa
5、shington, DC 20005. Printed in the United States of America Reference number ISO/IEC 11 179-4:1995(E) Copyright American National Standards Institute Provided by IHS under license with ANSI Licensee=USN Ship Repair Facility Yokosuka/9961031100 Not for Resale, 05/09/2007 00:00:22 MDTNo reproduction o
6、r networking permitted without license from IHS -,-,- ISO/zEC 11 179-4: 1995 (E) Contents Foreword 111 Introduction iv . 1. Scope 2. Normative references . 3. Definitions . 4. 5. Requirements . Summary of data definition rules and guidelines . Annex A Bibliography . 13 0 ISO/IEC 1995 All rights rese
7、rved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from the publisher. ISO/IEC Copyright Office Case postale 56 CH-121 I Genbve 20 * Swi
8、tzerland Printed in Switzerland Copyright American National Standards Institute Provided by IHS under license with ANSI Licensee=USN Ship Repair Facility Yokosuka/9961031100 Not for Resale, 05/09/2007 00:00:22 MDTNo reproduction or networking permitted without license from IHS -,-,- o ISO/IEC ISOAEC
9、 11179-41995 (E) Foreword IS0 (the International Organization for Standardization) and IEC (the International Electrotechnical Commission) form the specialized system for worldwide standardization. National bodies that are members of IS0 or IEC participate in the development of International Standar
10、ds through technical committees established by the respective organization to deal with particular fields of technical activity. IS0 and IEC technical committees collaborate in fields of mutual interest. Other international organizations, governmental and non-governmental, in liaison with IS0 and IE
11、C, also take part in the work. In the field of information technology, IS0 and IEC have established ajoint technical committee, ISO/IEC JTCl. Draft international Standards adopted by the joint technical committee are circulated to national bodies for voting. Publication as an International Standard
12、requires approval by at least 75% of the national bodies casting a vote. International Standard ISO/IEC 11 179-4 was prepared by Joint Technical Committee ISO/IEC JTC 1, Irflormation technology, SC 14, Data element principles. ISO/IEC 11 179 consists of the following parts, under the general title I
13、nformation technology - Specification and standardization of data elements: - Part I: Framework for the generation and standardization of data elements - Part 2: Classification of concepts for the identification o f domains - Part 3: Basic attributes of data elements - Part 4: Rules and guidelines f
14、or the formulation of data definitions - Part 5: Naming and identification principles for data elements - Part 6: Registration of data elements Annex A of this part of ISO/IEC 11 179 is for information only. . 111 Copyright American National Standards Institute Provided by IHS under license with ANS
15、I Licensee=USN Ship Repair Facility Yokosuka/9961031100 Not for Resale, 05/09/2007 00:00:22 MDTNo reproduction or networking permitted without license from IHS -,-,- ISO/IEC 11 179-4: 1995 (E) o ISO/IEC Introduction The purpose of a data element definition is to define the meaning of a data element.
16、 To ensure consistency and quality, this part of ISOAEC 11 179 provides rules and guidelines for the construction of well-formed data element definitions. Precise and unambiguous data element definitions are one of the most critical aspects of ensuring data shareability. When two or more parties exc
17、hange data, it is essential that all are in explicit agreement on the meaning of that data. One of the primary vehicles for carrying the datas meaning is the data element definition. Therefore, it is mandatory that every data element have a well-formed definition; one that is clearly understood by e
18、very user. Poorly formulated data element definitions foster misunderstandings and ambiguities and often inhibit successfd communication. This part of ISO/IEC 11 179 contains both rules and guidelines. These apply to the formulation of definitions of data elements used in information processing syst
19、ems and information interchange. Rules are mandatory and testable for compliance. principles that shall be followed. Objective test criteria can be established for rules. Conformance with guidelines is assessed by judgement of reasonableness. Guidelines are The data element names in this part of ISO
20、/IEC 11 179 do not follow a particular syntax. The term data element refers to data element type; the shorter term is used for convenience. iv Copyright American National Standards Institute Provided by IHS under license with ANSI Licensee=USN Ship Repair Facility Yokosuka/9961031100 Not for Resale,
21、 05/09/2007 00:00:22 MDTNo reproduction or networking permitted without license from IHS -,-,- INTERNATIONAL STANDARD 0 ISODEC ISO/IEC 11179-4:1995(E) Information technology - Specification and standardization of data elements Part 4: Rules and guidelines for the formulation of data definitions 1 Sc
22、ope This part of ISO/IEC 11179 specifies rules and guidelines for constructing definitions for data elements. Only semantic structures of data element definitions are addressed; specifications for formatting the definitions are deemed unnecessary for the purposes of this part of ISOAEC 11 179. Altho
23、ugh these definitional rules and guidelines pertain to data elements, they can also be applied in formulating definitions for other types of data constructs such as entity types, entities, relationships, attributes, object types (or classes), objects, segments, composites, code entries, and messages
24、. The definitional rules and guidelines in this part of ISO/IEC 11 179 do not always apply to terminological definitions found in glossaries and language dictionaries. Differences exist between the rules that apply in a language dictionary, and the rules that apply in a data dictionary. For example,
25、 terms in a language dictionary may have multiple definitions in the dictionary, whereas data dictionary definitions must be unique within a dictionary and have a single meaning. Many data element definitions include terms that themselves need to be defined (e.g., charge, “allowance“, “delivery“). S
26、ome of these terms may have different definitions in different industrial sectors. Therefore, there is a need for most data dictionaries to establish an associated glossary of terms used in the definitions. The area(s) of use for each term is identified in the glossary. 2 Normative references The fo
27、llowing standards contain provisions which, through reference in this text, constitute provisions of this part of ISOAEC 11 179. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this part of ISO/IEC 11 179 are en
28、couraged to apply the most recent editions of the standard indicated below. Members of IEC and IS0 maintain registers of currently valid International Standards. IS0 704: 1987 I, Principles and methods of terminology. IS0 1087: 1990 I), Terminology - Vocabulary. IS0 23 82-4: 1987, information proces
29、sing systems - Vocabulary - Part 4: Organization o f data. I) Ciirrently under revision. 1 Copyright American National Standards Institute Provided by IHS under license with ANSI Licensee=USN Ship Repair Facility Yokosuka/9961031100 Not for Resale, 05/09/2007 00:00:22 MDTNo reproduction or networkin
30、g permitted without license from IHS -,-,- ISO/IEC 11179-4:1995 (E) O ISODEC IS0 9735: 1988, Electronic data interchange for administration, commerce and transport (EDIFACT) - Application level syntax rules. IS0 1024 1 : 1992, International terminology standards - Preparation and layout. ISO/IEC 1 1
31、 179-3 : 1994, Information technology - Specification and standardization of data elements - Part 3: Basic attributes o f data elements. ANSI X3.172- 1990, American National Standard Dictionary for Information Systems (ANDIS). 3 Definitions For the purposes of this part of ISO/IEC 1 1 179, the follo
32、wing definitions apply, 3.1 attribute: A characteristic of an object or entity. 3.2 concept: A unit of thought constituted through abstraction on the basis of characteristics common to a set of objects. This definition may apply to other types of data constructs as identified in the Scope of this pa
33、rt of ISO/IEC 11 179. 3.3 data: A representation of facts, concepts, or instructions in a formalized manner suitable for communication, interpretation, or processing by humans or by automatic means (IS0 23 82-4). 3.4 data dictionary: A database used for data that refers to the use and structure of o
34、ther data; that is, a database for the storage of metadata (ANSI X3.172-1990). See data element dictionary. 3.5 data element: A unit of data for which the definition, identification, representation and permissible values are specified by means of a set of attributes. 3.6 data element dictionary: An
35、information resource that lists and defines all relevant data elements. Synonymous with data dictionary. NOTE - Data element dictionaries may exist at various levels, e.g. ISOAEC Coininittees, international associations, industry sectors, companies, application systems. 3.7 definition: A word or phr
36、ase expressing the essential nature of a person or thing or class of persons or things: an answer to the question “what is x?“ or “what is an x?“; a statement of the meaning of a word or word group Websters Third New International Dictionary of the English Language Unabridged, 19861. 3.8 domain: The
37、 set of possible data values of an attribute (ANSI X3.172-1990). 3.9 name: The primary means of identification of objects and concepts for humans. 2 Copyright American National Standards Institute Provided by IHS under license with ANSI Licensee=USN Ship Repair Facility Yokosuka/9961031100 Not for R
38、esale, 05/09/2007 00:00:22 MDTNo reproduction or networking permitted without license from IHS -,-,- o ISO/IEC ISO/IEC 11 179-4: 1995 (E) 4 Summary of data definition rules and guidelines A listing of the rules and guidelines without explanations is provided in this clause for convenience of the use
39、r. The intent is to facilitate ease of use of this document once an understanding of the rules and guidelines is achieved. Clause 5 describes each rule and guideline with an explanation and examples to ensure their exact meaning is understood. 4.1 Rules A data definition shall: a) be unique (within
40、any data dictionary in which it appears) b) be stated in the singular c) state what the concept is, not only what it is not d) be stated as a descriptive phrase or sentence(s) e) contain only commonly understood abbreviations 9 be expressed without embedding definitions of other data elements or und
41、erlying concepts 4.2 Guidelines A data definition should: a) state the essential meaning of the concept b) be precise and unambiguous c) be concise d) be able to stand alone e) be expressed without embedding rationale, fnctional usage, domain information, or procedural information 9 avoid circular r
42、easoning g) use the same terminology and consistent logical structure for related definitions 3 Copyright American National Standards Institute Provided by IHS under license with ANSI Licensee=USN Ship Repair Facility Yokosuka/9961031100 Not for Resale, 05/09/2007 00:00:22 MDTNo reproduction or netw
43、orking permitted without license from IHS -,-,- ISO/IEC 11179-4:1995 (E) o ISO/IEC 5 Requirements 5.1 Premises Data elements exist and are used for specific purposes. Differences in use will require different operational manifestations of some rules and guidelines. For example, different levels of s
44、pecificity for data element definitions are generally required in different contexts. Guideline 5.3 .a ) below, provides an example of this need for varying levels of specificity for different definitions. The implementation of Guideline 5.3.a), “state the essential meaning of the concept“ is contex
45、t dependent. The primary characteristics deemed necessary to convey the essential meaning of a particular definition will vary according to the levei of generalization or specialization of the data element. The primary characteristics should include consideration of the relevance of any object class
46、, property and qualifier associated with the concepts being analyzed. Primary and essential characteristics for defining concepts such as airportt in the commercial air transportation industry might be specific, where a more general definition may be adequate in a different context. For a discussion
47、 of relationships between concepts in different contexts and how characteristics are used to differentiate concepts, see IS0 704, Clause 3. Definitions should be written to facilitate understanding by any user and by recipients of shared data. 5.2 Rules To facilitate understanding of the rules for c
48、onstruction of well-formed data element definitions, explanations and examples are provided below. Each rule is followed by a short explanation of its meaning. Examples are given to support the explanations. In all cases, a good example is provided to exemplifi the explanation. When deemed beneficial, a poor, but commonly used example is given to show how a definition should NOT be constructed. To frther explain the differences between the good and poor examples, examples are followed by a statement of rationale behind them. A data definition shall: a) be unique (within any data