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.

Technical Flow Chart

Flow chart is a diagrammatic representation of an algorithm and essential part of planning the system. Flow charts are widely used in technical analysis and programming for easy writing programs and explaining them to others. So, one of the most popular type of flow charts is Technical Flow Chart. Technical Flow Chart can be drawn by pencil on the paper, but it will be easier to use for designing a special software. ConceptDraw DIAGRAM diagramming and vector drawing software extended with Flowcharts Solution from the "Diagrams" Area of ConceptDraw Solution Park will be useful for this goal.

Data Flow Diagram

Data Flow Diagram (DFD) is the part of the Structured Systems Analysis and Design Methodology (SSADM), which is intended for information systems projection and analysis. Data Flow Diagrams allow graphically represent the data flows in information system and analyze the data processing during the structural projection. This type of diagrams lets visually show a work of information system and results of this work, it is often used in connection with human processes and can be displayed as Workflow diagram. Data Flow Diagram visualizes processes and functions, external entities, data depositories, and data flows connecting these elements and indicating direction and data character. Each of these elements used for DFD has its own graphical notation. There are two notations to draw DFDs - Yourdon & Coad and Gane & Sarson. ConceptDraw DIAGRAM extended with Data Flow Diagrams (DFD) solution from Software Developmant area is ideal for designing professional looking DFDs, which can be then easily exported in various formats.

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.

Data Flow Diagram Process

Data Flow Diagram (DFD) is a hierarchy of functional processes, connected by data flows. The purpose of this presentation is to show how each process converts its inputs into outputs and to identify relationships between these processes. DFD is convenient way of modeling and construction the information processes, it step-by-step illustrates the flow of information in a process. For construction a DFD traditionally are used two different notations, which appropriate to the methods of Yourdon-Coad and Gane-Sarson. These notations slightly different from each other by graphical representation of symbols for processes, data stores, data flow, external entities. When designing a DFD it is required to decompose the system into the components (sub-systems), for explaining a complex system you may need represent numerous levels. The Data Flow Diagrams solution from ConceptDraw Solution Park contains numerous predesigned DFD symbols for both notations, which help easy and effectively design professional-looking Data Flow Diagrams (DFDs) and DFD Process Diagrams.

DFD Library — Design elements

Data Flow Diagrams (DFD) solution from the Software Development area of ConceptDraw Solution Park provides plenty of predesigned templates, samples and DFD vector design elements proposed by three DFD libraries. These DFD library objects are designed to help you effectively model the data flows and functional requirements for the business processes or systems, to design the Process-oriented models or Data-oriented models, Data flowcharts and Data process diagrams, Structured analysis diagrams and Information flow diagrams. There are two different notations used to draw the Data Flow Diagrams (Yourdon & Coad and Gane & Sarson). These notations define the different visual representations for the processes, data stores, data flows, and external entities. ConceptDraw DIAGRAM software provides you with possibility of designing professional-looking Data Flow Diagrams, DFD Models, Data Flow Process Diagrams using any of these notations. Simply drag the predesigned DFD flowchart symbols from the appropriate library and connect by arrows depicting the data flow from one step to another.