ERD Symbols and Meanings

Entity Relationship Diagram (ERD) is a popular software engineering tool for database modeling and illustration the logical structure of databases, which uses one of two notations - Chen's or Crow’s Foot. Crow's foot notation is effective when used in software engineering, information engineering, structured systems analysis and design. Each of these notations applies its own set of ERD symbols. Crow's foot diagrams use boxes to represent entities and lines between these boxes to show relationships. Varied shapes at the ends of lines depict the cardinality of a given relationship. Chen's ERD notation is more detailed way to represent entities and relationships. ConceptDraw DIAGRAM application enhanced with all-inclusive Entity-Relationship Diagram (ERD) solution allows design professional ER diagrams with Chen's or Crow’s Foot notation on your choice. It contains the full set of ready-to-use standardized ERD symbols and meanings helpful for quickly drawing, collection of predesigned ERD samples, examples and templates. ConceptDraw Pro is a great alternative to Visio for Mac users as it offers more features and can easily handle the most demanding professional needs.

Example of DFD for Online Store (Data Flow Diagram)

Data Flow Diagram (DFD) is a methodology of graphical structural analysis and information systems design, which describes the sources external in respect to the system, recipients of data, logical functions, data flows and data stores that are accessed. DFDs allow to identify relationships between various system's components and are effectively used in business analysis and information systems analysis. They are useful for system’s high-level details modeling, to show how the input data are transformed to output results via the sequence of functional transformations. For description of DFD diagrams are uses two notations — Yourdon and Gane-Sarson, which differ in syntax. Online Store DFD example illustrates the Data Flow Diagram for online store, the interactions between Customers, Visitors, Sellers, depicts User databases and the flows of Website Information. ConceptDraw DIAGRAM enhanced with Data Flow Diagrams solution lets you to draw clear and simple example of DFD for Online Store using special libraries of predesigned DFD symbols.

ConceptDraw DIAGRAM ER Diagram Tool

Entity-relationship model, also called ER-model, is the main tool of domain modeling on the stage of conceptual design. The modeling of domain data structures is based on the use of graphical tools - Entity-Relationship diagrams (ER-diagrams). The core concepts of ER-Diagram are entity, attribute and relationship. ER-diagram lets visually represent the entities, helps effectively document all properties of designed system and to detail the data storages. To represent the elements at ER-model are commonly used Chen’s notation and Crow’s foot notation, each has its pros and cons. The entity on ER-diagram is represented in the form of rectangle, which specifies its name. An attribute is a property of the entity and relationship is an interaction between the entities. The relationship between two entities is called binary, between more than two entities - ternary. Specific software, such as ConceptDraw DIAGRAM with Entity-Relationship Diagram (ERD) solution from ConceptDraw Solution Park is helpful for easy creation Entity-Relationship Diagrams.

DFD Flowchart Symbols

A Data Flow Diagram (DFD) is a graphical technique which allows effectively model and analyze the information processes and systems. The ability to fast and easy create the DFDs is made possible with Data Flow Diagrams solution from the Software Development area of ConceptDraw Solution Park. For designing the Data Flow Diagrams are used simple DFD flowchart symbols which are connected each other by arrows depicting the data flow from one step to another.

Booch OOD Diagram

The vector stencils library Booch OOD from the solution Software Engineering contains specific symbols of the Booch method such as class symbols, association symbols, aggregation symbols for ConceptDraw DIAGRAM diagramming and vector drawing software. The Software Engineering solution is contained in the Software Development area of ConceptDraw Solution Park.

Yourdon and Coad Diagram

The vector stencils library Yourdon and Coad Notation from the solution OOAD contains specific symbols of the Yourdon and Coad notation such as data store symbol, data process symbol, loop symbol for ConceptDraw DIAGRAM diagramming and vector drawing software. The OOAD solution is contained in the Software Development area of ConceptDraw Solution Park.

Network Topology Mapper

Network Topology in communication networks, a topology is a usually schematic description of the arrangement of a network, including its nodes and connecting lines. There are two ways of defining network geometry: the physical topology and the logical topology. Network Topology Mapper offers extensive drawing tools professional-looking network diagrams quickly and easily allowing you to clearly represent and communicate network architecture, topology, and design to engineers, stakeholders and end-users.

Data Flow Diagrams

Data Flow Diagram (DFD) is a special chart type which lets graphically illustrate the "flow" of data through an information system. So the Data Flow Diagrams can be successfully used for visualization of data processing or structured design, for creation an overview of the system, for business process modeling, for exploring the high-level design in terms of data flows and documenting the major data flows. Inclusion of powerful Data Flow Diagrams solution to the Software Development area of ConceptDraw Solution Park makes the ConceptDraw DIAGRAM a beneficial data flow diagramming software and supplies it with numerous collection of quick-start templates, professionaly designed samples, and extensive range of ready-for-use vector objects consisting the Data Flow Diagrams, Gane-Sarson Notation, and Yourdon and Coad Notation libraries. Use the ConceptDraw DIAGRAM application to design easy and quickly the Data Flow Diagrams including the data storages, data flows, external entities, functional transforms, control transforms and signals.

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.

System Design

ConceptDraw DIAGRAM diagramming and vector drawing software supplied with Specification and Description Language (SDL) solution from the Engineering area of ConceptDraw Solution Park offers the set of useful tools which make it ideal System Design Software.