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 PRO software.

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 PRO 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.

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

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 PRO diagramming and vector drawing software and Data Flow Diagram solution.

ORM Diagram

The vector stencils library ORM Diagrams from the solution Software Development contains specific ORM symbols for ConceptDraw PRO diagramming and vector drawing software. The Software Development solution is contained in the ConceptDraw Solution Park.

Notation & Symbols for ERD

The ER diagram is constructed from the specific ERD graphic elements. There are used 2 types of ERD notations: Chen and Crow's Foot. A complete set of work flow shapes, notation & symbols for ERD, entity relationship stencils, included in Entity-Relationship Diagram (ERD) solution for ConceptDraw PRO software, makes drawing diagrams based on ERD notation as smooth as possible.

UML Notation

Unified Modeling Language (UML) is an open standard, the language of graphic description used for modeling objects in a field of software development and software engineering. It was created for definition, specification, visualization, designing and documenting software systems, as a unification of three object-oriented technologies Booch, OMT and OOSE, and uses the defined graphic notation for creating the visual models of object-oriented software systems. Description of UML consists of two parts, interactive and supplementing each other: UML semantics, which represents a certain metamodel, defines the abstract syntax and semantics of terms of object modeling with UML, and UML notation that is a graphic notation for visual representation of UML semantics. The powerful tools of the Rapid UML solution included to ConceptDraw Solution Park make the ConceptDraw PRO diagramming and vector drawing software the best for easy applying the UML notation when creating the visual models of object-oriented software systems and designing different kinds of UML diagrams.