Search results
Results from the WOW.Com Content Network
Diagrams created to represent attributes as well as entities and relationships may be called entity-attribute-relationship diagrams, rather than entity–relationship models. An ER model is typically implemented as a database. In a simple relational database implementation, each row of a table represents one instance of an entity type, and each ...
An entity–relationship model (ERM) is an abstract conceptual representation of structured data. Entity–relationship modeling is a relational schema database modeling method, used in software engineering to produce a type of conceptual data model (or semantic data model ) of a system, often a relational database , and its requirements in a ...
Entity–relationship modeling is a database modeling method, used to produce a type of conceptual schema or semantic data model of a system, often a relational database, and its requirements in a top-down fashion. Diagrams created by this process are called entity-relationship diagrams, ER diagrams, or ERDs.
A sample ER diagram. Database requirements for a CD collection in EXPRESS-G notation.. In 1976, an entity-relationship (ER) graphic notation was introduced by Peter Chen.He stressed that it was a "semantic" modelling technique and independent of any database modelling techniques such as Hierarchical, CODASYL, Relational etc. [2] Since then, languages for information models have continued to ...
General-purpose freeware diagram editor; Can be used to draw different kinds of diagrams: flowcharts, computer network diagrams, UML diagrams, BPMN diagrams, mind maps, organization charts, entity relationship diagrams and many others; Mind42: Proprietary: Mind mapping: Web browser: Yes Yes Yes Browser-based collaborative web application
Download QR code; In other projects Appearance. move to sidebar hide ... Entity–relationship model; Metadata. This file contains additional information, probably ...
The enhanced entity–relationship (EER) model (or extended entity–relationship model) in computer science is a high-level or conceptual data model incorporating extensions to the original entity–relationship (ER) model, used in the design of databases.
To produce the logical specification, the analyst builds the required logical models for both the data-flow diagrams (DFDs) and the Logical Data Model (LDM), consisting of the Logical Data Structure (referred to in other methods as entity relationship diagrams) and full descriptions of the data and its relationships. These are used to produce ...