ERD Symbols and Meanings

Entity Relationship Diagram Symbols and Meaning - crow's foot notation

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.

How to Build an Entity Relationship Diagram (ERD)

Design elements - ER diagram (Chen notation)

"Chen's notation for entity–relationship modeling uses rectangles to represent entity sets, and diamonds to represent relationships appropriate for first-class objects: they can have attributes and relationships of their own. If an entity set participates in a relationship set, they are connected with a line.
Attributes are drawn as ovals and are connected with a line to exactly one entity or relationship set.
Cardinality constraints are expressed as follows:
- a double line indicates a participation constraint, totality or surjectivity: all entities in the entity set must participate in at least one relationship in the relationship set;
- an arrow from entity set to relationship set indicates a key constraint, i.e. injectivity: each entity of the entity set can participate in at most one relationship in the relationship set;
- a thick line indicates both, i.e. bijectivity: each entity in the entity set is involved in exactly one relationship.
- an underlined name of an attribute indicates that it is a key: two different entities or relationships with this attribute always have different values for this attribute.
Attributes are often omitted as they can clutter up a diagram; other diagram techniques often list entity attributes within the rectangles drawn for entity sets." [Entity–relationship model. Wikipedia]
The vector stencils library ERD, Chen's notation contains 13 symbols for drawing entity-relatinship diagrams using the ConceptDraw PRO diagramming and vector drawing software.
The example "Design elements - ER diagram (Chen notation)" is included in the Entity-Relationship Diagram (ERD) solution from the Software Development area of ConceptDraw Solution Park.

Chen's ERD

Used Solutions

AREA_SOFTWARE_DEVELOPMENT >

Chen Notation

Process Flowchart

The main reason of using Process Flowchart or PFD is to show relations between major parts of the system. Process Flowcharts are used in process engineering and chemical industry where there is a requirement of depicting relationships between major components only and not include minor parts. Process Flowcharts for single unit or multiple units differ in their structure and implementation. ConceptDraw PRO is Professional business process mapping software for making Process flowcharts, Process flow diagram, Workflow diagram, flowcharts and technical illustrations for business documents and also comprehensive visio for mac application. Easier define and document basic work and data flows, financial, production and quality management processes to increase efficiency of your business with ConcepDraw PRO. Business process mapping software with Flowchart Maker ConceptDraw PRO includes extensive drawing tools, rich examples and templates, process flowchart symbols and shape libraries, smart connectors that allow you create the flowcharts of complex processes, process flow diagrams, procedures and information exchange. Process Flowchart Solution is project management workflow tools which is part ConceptDraw Project marketing project management software. Drawing charts, diagrams, and network layouts has long been the monopoly of Microsoft Visio, making Mac users to struggle when needing such visio alternative like visio for mac, it requires only to view features, make a minor edit to, or print a diagram or chart. Thankfully to MS Visio alternative like ConceptDraw PRO software, this is cross-platform charting and business process management tool, now visio alternative for making sort of visio diagram is not a problem anymore however many people still name it business process visio tools.