Developing Entity Relationship Diagrams
Entity Relationship diagrams are the powerful tool for clear and visual modeling the relationships between database entities. When developing Entity Relationship Diagrams are used a set of common block objects and lines to describe the structure of a database.
Use the ConceptDraw DIAGRAM software extended with Entity-Relationship Diagram (ERD) solution from the Software Development area of ConceptDraw Solution Park for designing ER diagrams, which offers the predesigned commonly used Entity relationship symbols and ER objects. Thanks to them you can make the ERDs easy understandable for all your colleagues.
Sample 1. Entity Relationship Diagram (ERD), crow's foot notation
How to Build an Entity Relationship Diagram
When you need to visually represent the structure of relational database, Entity relationship diagram (ERD) is the best type of diagram for that case.
Most entity-relationship diagrams can be built with objects from Flowchart solution or ERD Solution which contains inbuilt templates. Follow these steps to create your own custom ERD diagram.
Don't be frightened if it looks complex, ConceptDraw DIAGRAM makes it easy to create an ERD, and hundreds of other diagrams, in minutes.
- Start drawing with Entity object from Crow's foot ERD object.
Note: This object contains several levels:
1 - object itself
2 - lines in the object
3 - separate cell. - It is possible to set different setting to each level.
- To switch from level to level, click on object with separate clicks when it's selected.
- Add text.
- Change object's color.
- Copy Teachers table.
- Add new rows via drop-down menu.
Note: Adding and removing is always performed from a bottom row. - New added row will have same preferences as bottom one.
- Paste copied table as many times as you need.
- Filling the table.
Note: To fill a separate cell, select it clicking with 3 separate clicks. - Delete excess rows via drop-down menu for each table.
- Use M:1 (many-to-one) connector from ERD Crow’s Foot Notation library.
- Connect needed rows of tables.
- If you want to change connectors' type, select all connectors with held Shift button and click on Smart connector icon at ribbon.
- To change connectors' elbow position, pull the yellow control dot.
- Select tables from left and set the same distribution.
- You may block the horizontal moving for object, so figure might be moved only vertically.
- Use M:M (many-to-many) connector from ERD Crow’s Foot Notation library.
- Set the needed connection.
Note: When connector's end reaches connection point, it changes its appearance.
- Edit connector's path manually with yellow control dots.
- Select all with command+A.
- Inspectors - Line - remove object lines (stroke).
- Export your document to one of graphic formats.
- Set the format and quality.
- Your file is ready!
The Entity-Relationship Diagram (ERD) solution from ConceptDraw Solution Park extends ConceptDraw DIAGRAM ector graphics and diagramming software with the ability to describe successfully a database using the Entity-Relationship model and easy create ERD.
Video. How to Build an Entity Relationship Diagram (2min 05sec)
Use ConceptDraw DIAGRAM enhanced with Entity Relationship Diagram (ERD) solution to draw you own ER diagrams using Chen's or Crow's Foot notations.
NINE RELATED HOW TO's:
Software Diagram Examples and Templates →
ConceptDraw DIAGRAM is a powerful tool for business and technical diagramming. Software Development area of ConceptDraw Solution Park provides 5 solutions: Data Flow Diagrams, Entity-Relationship Diagram (ERD), Graphic User Interface, IDEFO Diagrams, Rapid UML.
Picture: Software Diagram Examples and Templates
Related Solution:
Education Information →
The Education Information is multifariuos and can be often represented in various forms. Еру the most successful ways of presentation the information and data are various illustrations, diagrams and colorful education infographics which you can easily make in ConceptDraw DIAGRAM software extended with Education Infographics Solution from the Business Infographics Area.
Picture: Education Information
Related Solution:
UML Use Case Diagram Example. Social Networking Sites Project →
UML Diagrams Social Networking Sites Project. This sample was created in ConceptDraw DIAGRAM diagramming and vector drawing software using the UML Use Case Diagram library of the Rapid UML Solution from the Software Development area of ConceptDraw Solution Park. This sample shows the Facebook Socio-health system and is used at the projection and creating of the social networking sites.
Picture: UML Use Case Diagram Example. Social Networking Sites Project
Related Solution:
Design Element: Chen for Entity Relationship Diagram - ERD →
It is very difficult to get into database model idea without any examples. To create one, you can use Chen’s notation for Entity Relationship Diagrams (ERD) and try to see all the peculiarities yourself. This notation describes entities and relations as basic geometric shapes like rectangles and diamonds. Chen notation for Entity-relationship diagrams is used for designing relational databases. It depicts the database entities as a set of subjects. For example events, people, ideas, etc. All entities has common characteristics (attributes). Any object of the system is identified as the sole and unique. The name of entity should indicate the class or type of the the whole object, not a given example. The connection commonly represents a relationship between entities. Conceptdraw Entity-Relationship Diagrams (ERD) solution provides the libraries with ready-to-use ERD element fitting Chen's notation objects and relationships.
Picture: Design Element: Chen for Entity Relationship Diagram - ERD
Related Solution:
Electrical Symbols — Resistors →
A resistor is a passive two-terminal electrical component that implements electrical resistance as a circuit element. Resistors may be used to reduce current flow, and, at the same time, may act to lower voltage levels within circuits. In electronic circuits, resistors are used to limit current flow, to adjust signal levels, bias active elements, and terminate transmission lines among other uses. Fixed resistors have resistances that only change slightly with temperature, time or operating voltage. Variable resistors can be used to adjust circuit elements (such as a volume control or a lamp dimmer), or as sensing devices for heat, light, humidity, force, or chemical activity. 26 libraries of the Electrical Engineering Solution of ConceptDraw DIAGRAM make your electrical diagramming simple, efficient, and effective. You can simply and quickly drop the ready-to-use objects from libraries into your document to create the electrical diagram.
Picture: Electrical Symbols — Resistors
Related Solution:
Pyramid Diagram →
This pyramid chart example is supplied with the ConceptDraw Pyramid Diagrams solution. This is a model of Information Management Systems classification. It is made in a form of a four-level pyramid. The top level shows the information system developed for an executive management. Below, there is a level depicting the system of decision making process for the managers of the senior level. A schematic representation of the middle management information system, following to logic, is in the middle of the pyramid. And at least, the lowermost level represents an information processing system for employees.
Picture: Pyramid Diagram
Related Solutions:
Network Topologies →
When describing any computer network, we imagine a set of devices and nodes, arranged in some way. Talking about network structures, we should distinguish physical and logical network topologies, as physical topology is about devices location and logical topology illustrates data flow. In the same time, they do not have to match, and some devices, such as repeaters, may have a physical star layout, but a bus logical topology. There are two main types of computer network topologies: Physical topology that show the physical organization of a network - equipment and types of connections. Star network topology involves a set of devices that is connected to a single hub (router). Ring network topology means that, devices connected according this topology have two connections, connecting with nearby devices to make a loop. Bus network topology is the topology presented at the current diagram. It is similar to a ring topology. The difference is that data moves up and down a linear connection, copying itself where network equipment works as bus-stations along the way. This network topology can be used for small network, or when adding an extra device into a network.
Picture: Network Topologies
Related Solution:
ConceptDraw
DIAGRAM 15