Data Flow Diagram (DFD)

A Data Flow Diagram (DFD) illustrates the flow of data through an information system, visualizes how the information is handled in terms of inputs and outputs, how the data enter to system and leave it. It is effective to use a Data Flow Diagram for creation the system's overview, to show the system's scope and boundaries. There are two different types of notations for DFDs: Yourdon-Coad and Gane-Sarson, which differ in visual representations for processes, data flow, data stores, external entities, etc. Thus, for example the processes are depicted as circles in Yourdon-Coad notation and as rounded squares in Gane-Sarson notation. Gane-Sarson notation is usually used for visualization information systems and Yourdon-Coad - for system analysis and design. The Data Flow Diagrams solution included to Software Development area of ConceptDraw Solution Park offers a lot of DFD templates, samples and examples, libraries of vector stencils for construction without efforts the DFDs according to both Gane-Sarson and Yourdon-Coad notations.

Structured Systems Analysis and Design Method (SSADM) with ConceptDraw DIAGRAM

Structured Systems Analysis and Design Method (abbr. SSADM) is a method developed in Great Britain and accepted in 1993 as a national standard for information systems development and analysis. SSADM is based on Data Flow Diagrams and is characterized with presence of clear sequence of steps at projecting, analysis, and documenting of information system. It involves 6 main stages: analysis of existing system or estimation of practicability, requirements definition, determination of technical requirements and equipment cost, development of logical data model, projecting of logical requirements and specification them, physical projecting. Each of them is also divided into several steps defining the tasks that should be fulfilled at a given stage. The most important SSADM elements are flows modeling with help of DFD, data logic modeling with help of LDS (Logical Data Structure) and description of entities behavior. Applying of SSADM is easy with ConceptDraw DIAGRAM diagramming and vector drawing software and Data Flow Diagram solution.

Data Flow Diagram Symbols. DFD Library

Data Flow Diagrams graphically represent the information transfers and process steps of a system. They visually depict how data are processed by a system in terms of inputs and outputs, how occurs the input in a system, how the data flow through an information system and where they are stored, and how occurs output from the system. DFDs give the overview of the system and models the processes aspects, they are maintained with other methods of structured systems analysis. The main goal of DFDs is achievement of understanding between developers and users. For their construction are used two notations - Gane-Sarson and Yourdon, each of them uses its own set of symbols. Data Flow Diagrams solution from Software Development area extends the ConceptDraw DIAGRAM software with templates, samples, and predesigned libraries of data flow diagram symbols for both notations, allowing you easy design the process-oriented and data-oriented models, draw the Data Flow Diagrams, Data Flowcharts, Data Process Diagrams, Information Flow Diagrams, Structured Analysis Diagrams, etc.

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.

Types of Flowcharts

A Flowchart is a graphical representation of process, algorithm, workflow or step-by-step solution of the problem. It shows the steps as boxes of various kinds and connects them by arrows in a defined order depicting a flow. There are twelve main Flowchart types: Basic Flowchart, Business Process Modeling Diagram (BPMN), Cross Functional Flowchart, Data Flow Diagram (DFD), IDEF (Integrated DEFinition) Flowchart, Event-driven Process Chain (EPC) Diagram, Influence Diagram (ID), Swimlane Flowchart, Process Flow Diagram (PFD), Specification and Description Language (SDL) Diagram, Value Stream Mapping, Workflow Diagram. Using the Flowcharts solution from the Diagrams area of ConceptDraw Solution Park you can easy and quickly design a Flowchart of any of these types. This solution offers a lot of special predesigned vector symbols for each of these widely used notations. They will make the drawing process of Flowcharts much easier than ever. Pay also attention for the included collection of ready Flowchart examples, samples and quick-start templates. This is business process improvement tools. If you are looking for MS Visio for your Mac, then you are out of luck, because it hasn't been released yet. However, you can use Visio alternatives that can successfully replace its functions. ConceptDraw DIAGRAM is an alternative to MS Visio for Mac that provides powerful features and intuitive user interface for the same.

Data Flow Diagram Model

Data Flow Diagram (DFD) is a technique of graphical structural analysis, describing the sources external to the system, recipients of data, also logical functions, data flows and data stores that are accessed. The DFD's goal is to show how each process converts its inputs into the outputs and to identify relationships between these processes, at this make the system's description clear and understandable at every level of detail. Historically happened that for describing Data Flow Diagrams are used two notations - Yourdon and Gane-Sarson that differ each from other by graphical representation of symbols. The DFD model, like most other structural models is a hierarchical model. Each process can be subjected to decomposition on the structural components, the relationships between which in the same notation can be shown on a separate diagram. Typically, several DFD models are built when modeling the system. ConceptDraw DIAGRAM software enhanced with Data Flow Diagrams solution ideally suits for creation DFD models and professional drawing Data Flow Diagrams.

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.

ConceptDraw DIAGRAM DFD Software

Our DFD software ConceptDraw DIAGRAM allows you to quickly create DFD with data storages, external entities, functional transforms, data flows, as well as control transforms and signals. DFD program ConceptDraw DIAGRAM has hundreds of templates, and a wide range of libraries with all nesassary ready-made drag-and-drop.

DFD Library System

The Data Flow Diagram (DFD) is a graphical technique used for effective modeling and analyzing the information processes and systems. Having at the disposal the DFD library system and newest powerful tools of ConceptDraw DIAGRAM diagramming and vector drawing software supplied with Data Flow Diagrams (DFD) solution from the Software Development area of ConceptDraw Solution Park, you can design fast and easy the Data flow diagrams, Data flowcharts, Data flow models, Data flow process diagrams, Process-oriented models, Data-oriented models, Data process diagrams, Structured analysis diagrams, Information flow diagrams of any type and complexity. For designing the Data Flow Diagrams in ConceptDraw DIAGRAM software are used the simple DFD flowchart symbols from the offered DFD libraries - Data Flow Diagram (DFD) library, Yourdon and Coad Notation library, and Gane-Sarson Notation library. The DFD objects are need to be connected each other by the arrows to depict the data flow from one step to another, that you can do in seconds in ConceptDraw DIAGRAM , as well as set desired design of your diagram.