Entity Relationship Diagram Examples

Creation of Entity-Relationship (ER) model is a visual representation the structure of a business database, where data equates to entities or objects, which are linked by defined relationships expressing dependencies and requirements. By the nature, the ER model is an abstract visualization, a first step in design process towards creating a logical and functional database. ConceptDraw DIAGRAM professional software gives the ability to effectively describe a database using the Entity-Relationship model. Included to ConceptDraw Solution Park, the Entity-Relationship Diagram (ERD) solution contains the set of predesigned vector icons advocated by Chen's and Crow’s Foot notations that both can be used for data modeling and describing a database. Entity-Relationship Diagram (ERD) solution includes also helpful templates and incredibly large collection of varied Entity Relationship Diagram examples and samples offered at ConceptDraw STORE. Each of them can be used to develop your own model of a database of arbitrary complexity.

Entity Relationship Diagram - ERD - Software for Design Crows Foot ER Diagrams

ER-model is a data model which lets describe the conceptual schemes in a specific subject area. It can help to highlight the key entities and specify relationships that can be established between these entities. During the database design, it is realized the transformation of ER model into certain database scheme based on the chosen data model (relational, object, network, etc.). There are used two notations for ERDs: Crow's Foot and Chen's. Crow's Foot notation proposed by Gordon Everest represents the entity by rectangle containing its name (name must be unique within this model), and relation - by the line which links two entities involved in relationship. The relationship's plurality is graphically indicated by a "plug" on the end of the link, the optionality - by a circle. Entity-Relationship Diagrams based on Crow's Foot notation can be easily drawn using the ConceptDraw DIAGRAM. Extended with Entity-Relationship Diagram (ERD) solution, it is the best ERD diagrams software with powerful tools and ready design elements for Crow's Foot and Chen notations.

Entity Relationship Diagram Symbols

The semantic modeling method nowadays is successfully applied in database structure design. It is effective method of modeling the data structures, which is based on the meaning of these data. As a tool of semantic modeling, there are used different types of Entity-Relationship Diagrams. Entity Relationship Diagram (ERD) is applied to visually and clearly represent a structure of a business database. The main components of ERDs are: entity, relation and attributes. An entity is a class of similar objects in the model, each entity is depicted in the form of rectangle and has the name expressed by a noun. Relation is shown in the form of non-directional line that connects two entities. There are several notation styles used for ERDs: information engineering style, Chen style, Bachman style, Martin Style. The Entity Relationship Diagram symbols used for professional ERD drawing are predesigned by professionals and collected in the libraries of the Entity-Relationship Diagram (ERD) solution for ConceptDraw DIAGRAM software.

Design Element: Crows Foot for Entity Relationship Diagram - ERD

Entity-Relationship Diagram (ERD) is ideal tool that helps execute the detalization of data warehouse for a given designed system, lets to document the system's entities, attributes (objects' properties), and their interactions each other (relationships). Creation of an ERD requires the choice of specific set of notations, which the best suits for your database design. Two notations - Chen’s and Crow's Foot are applied for ERDs design. Chen's notation was developed first and has linguistic approach, the boxes represent the entities and are considered as nouns, relationships between them are shown as diamonds in a verb form. Over time Chen’s style was adapted into the popular standard - Crow’s Foot notation, where entities are shown as boxes and relationships - as labeled lines. ConceptDraw DIAGRAM software supplied with Entity-Relationship Diagram (ERD) solution offers samples and templates of ER diagrams, and also ready-to-use vector design elements - ERD Crow′s Foot and Chen's notation icons for easy designing your own ER diagrams for depicting databases.

Data Flow Diagram Examples

Data flow diagrams (DFDs) are effective to reveal relationships among the various components in a program or system. This type of diagrams is an important and useful technique for modeling an information system, its process aspects, for showing a system as a single high-level process. DFD lets illustrate the flow of data, how the input data are transformed to output results across the sequence of functional transformations. DFD consists of four major components: entities, processes, data stores, data flows. When you need to draw a Data Flow Diagram the ConceptDraw DIAGRAM diagramming and vector drawing software extended with Data Flow Diagrams solution will be helpful for you. Providing numerous collection of Data Flow Diagram examples, samples, templates and ready-to-use vector DFD symbols, Data Flow Diagrams solution ensures you with all needed tools for easy designing DFDs according to Gane-Sarson or Yourdon-Coad notation on your choice. Any from offered predesigned DFD examples can become a perfect base for your own diagram.

Network Diagram Software Physical Network Diagram

ConceptDraw Network Diagram Software is ideal for network engineers and network designers who need to draw Physical Network Diagrams.

UML Class Diagram Generalization Example UML Diagrams

This sample was created in ConceptDraw DIAGRAM diagramming and vector drawing software using the UML Class Diagram library of the Rapid UML Solution from the Software Development area of ConceptDraw Solution Park. This sample describes the use of the classes, the generalization associations between them, the multiplicity of associations and constraints. Provided UML diagram is one of the examples set that are part of Rapid UML solution.

Campus Area Networks (CAN). Computer and Network Examples

Campus Area Network (CAN) is a computer network which provides wireless access to the Internet or LAN for the users located in two or more buildings on the limited geographical area, or in the open space surrounding these buildings. Campus Area Network is usually set in campus of a university or college, but the same kind of planning and design can be applied for other purposes, for enterprises, office buildings, military bases, industrial complexes, public places like supermarkets, entertainment centers, etc. Another form of temporary CAN can exist during some special events such as rallies, music festivals. The elementary Campus Area Network can also arise spontaneously, due to the distance of spread the radio signals from the access points that are not limited by buildings walls. It is also sensible to have additional access points for the larger and more complex CANs, located at specially places chosen for serving clients. Design easy diagrams and schemes for the Campus Area Networks with Computer Network Diagrams solution for ConceptDraw DIAGRAM.