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entity-relationship diagram, ER-diagram, database ERD Entity-Relationship Diagram (ERD)

entity-relationship diagram, ER-diagram, database ERD
Entity-Relationship Diagram (ERD) solution extends ConceptDraw DIAGRAM software with templates, samples and libraries of vector stencils from drawing the ER-diagrams by Chen's and crow’s foot notations.
"Crow's Foot notation is used in Barker's Notation, SSADM and Information Engineering. Crow's Foot diagrams represent entities as boxes, and relationships as lines between the boxes. Different shapes at the ends of these lines represent the cardinality of the relationship." [Entity–relationship model. Wikipedia]
The vector stencils library ERD, crow's foot notation contains 18 symbols for creating the ER-diagrams using the ConceptDraw PRO diagramming nd vector drawing software.
The example"Design elements - ERD solution (crow's foot notation)" is included in the Entity-Relationship Diagram (ERD) solution from the Software Development area of ConceptDraw Solution Park.
Crow's foot ERD
Crow's foot ERD, entity,
"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
Chen's ERD, week key attribute, weak entity, relationship, multivalue attribute, key attribute, identifying relationship, entity, derived attribute, attribute, associative entity,

Software development with ConceptDraw DIAGRAM

Modern software development requires creation of large amount of graphic documentation, these are the diagrams describing the work of applications in various notations and cuts, also GUI design and documentation on project management. ConceptDraw DIAGRAM technical and business graphics application possesses powerful tools for software development and designing technical documentation for object-oriented projects. Solutions included to the Software Development area of ConceptDraw Solution Park provide the specialists with possibility easily and quickly create graphic documentation. They deliver effective help in drawing thanks to the included package of templates, samples, examples, and libraries with numerous ready-to-use vector objects that allow easily design class hierarchies, object hierarchies, visual object-oriented designs, flowcharts, GUI designs, database designs, visualize the data with use of the most popular notations, including the UML and Booch notations, easy manage the development projects, automate projection and development.
HelpDesk

How to Create an Entity-Relationship Diagram Using ERD Solution

An entity-relationship diagram (ERD)is used in a database modeling process. ERD diagram shows a graphical representation of objects or concepts within an information system and their relationships. The ability to describe a database using the Entity-Relationship model is delivered by the ConceptDraw ERD solution.