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Database Schema

The description of a database structure. It defines tables and fields and the relationship between them.

Datastore

An element used to define permanently stored data. A token of data that is stored in the Datastore is stored permanently. A token of data that comes out of the Datastore is a copy of the original data. The tokens imported are kept for the life of the Activity in which it exists.

Datatype

A descriptor of a set of values that lack identity and whose operations do not have side effects. Datatypes include primitive pre-defined types and user-definable types. Pre-defined types include numbers, string and time. User-definable types include enumerations.

Decision

An element of an Activity diagram that indicates a point of conditional progression: if a condition is true, then processing continues one way, if not, then another.

Defining Model (MOF)

The model on which a repository is based. Any number of repositories can have the same defining model.

Delegate

A connector that defines the internal assembly of a component's external ports and interfaces. Using a Delegate connector wires the internal workings of the system to the outside world, by a delegation of the external interfaces' connections.

Delegation

The ability of an object to issue a message to another object in response to a message. Delegation can be used as an alternative to inheritance.

Contrast: inheritance

Dependency

A relationship between two modeling elements, in which a change to one modeling element (the independent element) affects the other modeling element (the dependent element).

Deployment

A type of Dependency relationship that indicates the deployment of an artifact onto a node or executable target.

Deployment Diagram

A diagram that shows the configuration of run-time processing nodes and the components, processes, and objects that live on them. Components represent run-time manifestations of code units.

Deployment Specification

Specifies parameters guiding deployment of an artifact, as is common with most hardware and software technologies.

Derived Element

A model element that can be computed from another element, but that is shown for clarity or that is included for design purposes even though it adds no semantic information.

Design

The part of the software development process whose primary purpose is to decide how the system is to be implemented. During design, strategic and tactical decisions are made to meet the required functional and quality requirements of a system.

Design Time

Refers to something that occurs during a design phase of the software development process.

Development Process

A set of partially ordered steps performed for a given purpose during software development, such as constructing models or implementing models.

Diagram

A graphical presentation of a collection of model elements, most often rendered as a connected graph of arcs (relationships) and vertices (other model elements). UML supports 14 diagram types, and Enterprise Architect extends these with seven more. Add-Ins, technologies and profiles can provide further diagram types.

Diagram Gate

A simple graphical way to indicate the point at which messages can be transmitted into and out of Interaction Fragments.

Diagram View

The Enterprise Architect workspace area where the UML diagrams are displayed.

Disjoint Substate

A substate that cannot be held simultaneously with other substates contained in the same composite State.

Distribution Unit

A set of objects or components that are allocated to a process or a processor as a group. A distribution unit can be represented by a run-time composite or an Aggregate.

Domain

An area of knowledge or activity characterized by a set of concepts and terminology understood by practitioners in that area.

Dynamic Classification

A semantic variation of Generalization in which an object can change its classifier.