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Entity-Relationship Diagram (ERD)

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

entity-relationship diagram, ER-diagram, database ERD
An Entity-Relationship Diagram (ERD) is a visual presentation of entities and relationships. That type of diagrams is often used in the semi-structured or unstructured data in databases and information systems. At first glance ERD is similar to a flowch Read more

ConceptDraw PRO Database Modeling Software

ConceptDraw PRO is a very easy-to-use and intuitive database design tool which can save you hundreds of work hours. See database diagram samples created with ConceptDraw PRO database modeling database diagram software. Read more
"In software engineering, an entity–relationship model (ER model) is a data model for describing a database in an abstract way. ...
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]
This ERD example was redesigned using the ConceptDraw PRO diagramming and vector drawing software from the educational data base model. [www2.cs.uregina.ca/~bernatja/crowsfoot.html]
The example "Entity-relationship diagram (Crow's foot notation)" is included in the Entity-Relationship Diagram (ERD) solution from the Software Development area of ConceptDraw Solution Park. Read more
Crow's foot ERD
Crow's foot ERD, entity,
"An ER model is an abstract way of describing a database. In the case of a relational database, which stores data in tables, some of the data in these tables point to data in other tables - for instance, your entry in the database could point to several entries for each of the phone numbers that are yours. The ER model would say that you are an entity, and each phone number is an entity, and the relationship between you and the phone numbers is 'has a phone number'. Diagrams created to design these entities and relationships are called entity–relationship diagrams or ER diagrams.
Using the three schema approach to software engineering, there are three levels of ER models that may be developed. ...
Conceptual data model ... is the highest level ER model in that it contains the least granular detail but establishes the overall scope of what is to be included within the model set.
Logical ER model ... contains more detail than the conceptual ER model. In addition to master data entities, operational and transactional data entities are now defined.
The physical ER model is normally developed to be instantiated as a database. Therefore, each physical ER model must contain enough detail to produce a database and each physical ER model is technology dependent since each database management system is somewhat different.
Physical model ... is normally forward engineered to instantiate the structural metadata into a database management system as relational database objects such as database tables, database indexes such as unique key indexes, and database constraints such as a foreign key constraint or a commonality constraint." [Entity–relationship model. Wikipedia]
This crow's foot entity-relationship diagram (ERD) example "Educational data base" was created using the ConceptDraw PRO diagramming and vector drawing software extended with the Entity-Relationship Diagram (ERD) solution from the Software Development area of ConceptDraw Solution Park. Read more
ERD
ERD, entity,
"In software engineering, an entity–relationship model (ER model) is a data model for describing a database in an abstract way.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." [Entity–relationship model. Wikipedia]
This sample Chen's ER-diagram illustrates the structure of a typical MMORP game.
"Massively multiplayer online role-playing game (MMORPG) mixes the genres of role-playing video games and Massively multiplayer online games, possibly in the form of web browser-based games, in which a very large number of players interact with one another within a virtual world.
As in all RPGs, players assume the role of a character (often in a fantasy world or science-fiction world) and take control over many of that character's actions. MMORPGs are distinguished from single-player or small multi-player online RPGs by the number of players, and by the game's persistent world (usually hosted by the game's publisher), which continues to exist and evolve while the player is offline and away from the game." [Massively multiplayer online role-playing game. Wikipedia]
This ERD example was redrawn using the ConceptDraw PRO diagramming and vector drawing software from the Wikipedia file: ER Diagram MMORPG.png. [en.wikipedia.org/wiki/File:ER_Diagram_MMORPG.png]
This file is licensed under the Creative Commons Attribution-Share Alike 3.0 Unported license. [creativecommons.org/licenses/by-sa/3.0/deed.en]
This Chen's ERD example is included in the Entity-Relationship Diagram (ERD) solution from the Software Development area of ConceptDraw Solution Park. Read more
Chen's ERD
Chen's ERD, weak key attribute, weak entity, relationship, multivalue attribute, key attribute, identifying relationship, entity, derived attribute, attribute,

software development, software engineering Software Development Area

software development, software engineering
Solutions from the Software Development Area of ConceptDraw Solution Park collect templates, samples and libraries of vector stencils for drawing the software engineering diagrams and user interface design prototypes. Read more
"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 17 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. Read more
Crow's foot ERD
Crow's foot ERD, entity,

ConceptDraw Solution Park ConceptDraw Solution Park

ConceptDraw Solution Park
ConceptDraw Solution Park collects graphic extensions, examples and learning materials Read more

GUI development tool, GUI interface prototyping Graphic User Interface

GUI development tool, GUI interface prototyping
Graphic User Interface solution extends ConceptDraw PRO software with templates, samples and libraries of vector stencils for design of the GUI prototypes and diagrams for Windows, Mac OS and iOS software. Read more

data flow diagram, DFD templates Data Flow Diagrams (DFD)

data flow diagram, DFD templates
Data Flow Diagrams solution extends ConceptDraw PRO software with templates, samples and libraries of vector stencils for drawing the data flow diagrams (DFD). Read more

engineering, mechanical, electrical, chemical, process, diagram, scheme, technical, drawing Engineering

engineering, mechanical, electrical, chemical, process, diagram, scheme, technical, drawing
This solution extends ConceptDraw PRO v9.4 with the ability to visualize industrial systems in electronics, electrical, chemical, process, and mechanical engineering. Read more