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Entity Relationship Diagram Symbols

Entity Relationship Diagram Symbols
Creating an entity-relationship (ER) model is to visually represent the structure of a business database, where data equates to entities (or objects) that are linked by defined relationships expressing dependencies and requirements. By nature it is an abstract visualization, the first step in the design process towards creating a logical and functional database.
ERD symbols used for professional ERD drawing are collected in libraries from the Entity-Relationship Diagram (ERD) solution for ConceptDraw DIAGRAM.
This object-role modeling (ORM) diagram sample shows disjunctive mandatory role constraint.
It was designed on the base of the Wikimedia Commons file: 9 DisjunktyvusPrivalomumoRibojimas.jpg. [commons.wikimedia.org/ wiki/ File:9_ DisjunktyvusPrivalomumoRibojimas.jpg]
"2.7. Mandatory Role Constraints.
The ORM 1 tool indicates simple mandatory constraints by a solid dot either (a) at the intersection of an entity type shape and the line connecting it to a role, or (b) at the role end. Option (b) is needed to avoid ambiguity when an object type plays many mandatory roles whose connections to the object type are too close to distinguish which role the dot applies to. Currently, disjunctive mandatory (inclusive-or) constraints are depicted by placing the solid dot in a circle connected by dotted lines to the roles it applies to. ORM 2 retains this notation, except that the solid dot is consistently colored violet and a global configuration option determines the default placement of simple mandatory dots at the role or object type end. Users may override this global setting on an individual role basis." [www.orm.net/ pdf/ ORM2_ TechReport1.pdf]
The object-role model example "Disjunctive mandatory constraint ORM diagram" was designed using ConceptDraw PRO software extended with ORM Diagrams solution from Software Development area of ConceptDraw PRO Solution Park.
Object role modeling
Object role modeling, role connector, index annotation, entity, ORM diagrams, object-role modeling, disjunctive mandatory constraint, constraint connector, binary predicate, binary association,
Used Solutions

Network Diagram Software. LAN Network Diagrams. Physical Office Network Diagrams

LAN Network Diagram
ConceptDraw Network Diagramming Software with examples of WAN, LAN Diagrams. ConceptDraw Network Diagram is ideal for network engineers and network designers who need to draw Local Area Network diagrams, physical office network diagrams and Diagram for LAN.
How to Draw a Computer Network
How to Draw a Computer Network

ERD Symbols and Meanings

ERD Symbols and Meanings
Crow's foot notation is used in Barker's Notation, Structured Systems Analysis and Design Method (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.
The Chen's ERD notation is still used and is considered to present a more detailed way of representing entities and relationships.
To create an ERD, software engineers mainly turn to dedicated drawing software, which contain the full notation resources for their specific database design - ERD symbols and meanings. CS Odessa has released an all-inclusive Entity-Relationship Diagram (ERD) solution for their powerful drawing program, ConceptDraw DIAGRAM.
How to Build an Entity Relationship Diagram (ERD)
How to Build an Entity Relationship Diagram (ERD)

software engineering, data model, data modeling tools, orm Object-Role Modeling (ORM) Diagrams

software engineering, data model, data modeling tools, orm
Object-role Modeling (ORM) Diagram solution with powerful vector diagramming and data modeling tools, large quantity of specially developed samples and examples, and rich variety of vector objects corresponding to common ORM notation, ideally suits for developing the comprehensive, clear and visual Object-role Modeling (ORM) diagrams and schematics, understandable for all interested people from the different fields and business directions, for designing the ORM models, and demonstrating advantages from the use of ORM and its notation. It is intended for software developers and computer engineers, specialists in a field of Object-oriented programming (OOP), database architects, web-application constructors and developers, etc.

UML Use Case Diagram. Design Elements

UML Use Case Diagrams are used to illustrate the structure of arbitrarily complex systems and illustrates the service consumer - service provider relationship between components.

Diagramming Software for Design UML Use Case Diagrams

Use Case Diagrams describes the functionality provided by a system in terms of actors, their goals represented as use cases, and any dependencies among those use cases.

ORM Diagram

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

UML Use Case Diagrams

ConceptDraw has several examples that help you to start using software for designing UML Use Case Diagrams.

Financial Trade UML Use Case Diagram Example

This sample represents the actors, use cases and dependencies between them, and also the relationships between use cases. There are used dependency and use case generalization associations on this UML diagram. Use case generalization is used when you have two similar use cases, but one of them does more than another.
This sample shows the work of the Financial Trade sphere and can be used by trading companies, commercial organizations, traders, different exchanges.