DEC STD 065-0

This document, DEC STD 065-0 (Digital Standard Data Definitions), published by Digital Equipment Corporation in March 1991, defines the requirements for standardizing data object definitions within the company.

Its core purpose is to establish a framework for defining sharable and reusable data objects, including data elements, fields, data entities, relationships, and data models, to ensure consistency, facilitate system integration, promote efficient database design, and improve developer productivity across the corporation.

The standard applies to all data modeling activities within Digital and differentiates between two main types of data models:

1. Third Normal Form (3NF) Models: Business-focused, normalized representations of information.
2. Optimized Models: Transformations of 3NF models designed for specific application or implementation performance, ease-of-use, or security requirements.

Key requirements for all standard data object definitions include:

• A formal Business Name, Abbreviated Name, and Description.
• An Integrity Narrative detailing business rules and scope.
• A designated Controller responsible for the accuracy and usability of the definition.
• A Security Classification for both the data values and the metadata itself.
• A unique Data Object Identifier and Revision.

The document outlines specific requirements for each data object type:

• Data Models must include Entity-Relationship Diagrams and list all contained entities and associations.
• Entities (3NF or Optimized) must define primary keys and attributes, conforming to 3NF rules for 3NF entities.
• Associations represent relationships between entities, including Simple Relationships (binary, one-to-many, no attributes) and Complex Relationships (many-to-many, multi-entity, or with attributes), as well as Classifications and Subtyping for hierarchical groupings with inheritance.
• Elements are individual units of business data, defining logical properties and data format.
• Fields are implementation-specific representations of elements within a Data Description Language (DDL), distinguished as Standard Fields (direct translation of an element) or Nonstandard Fields (locally modified versions based on a Standard Field).

Responsibilities for implementing and enforcing this standard are distributed among the Enterprise Data Board (EDB) (governance, procedures, enforcement), Controllers (accuracy and usability of definitions), Information Systems Managers (ensuring compliance in system development), and Data Resource Specialists (creating, managing, and implementing data object definitions).