Made with
ConceptDraw
DIAGRAM 16

Entity-Relationship Diagram (ERD)
with ConceptDraw DIAGRAM

Entity-Relationship Diagram (ERD) serves for detailed description of structures and databases. An ERD represents a diagram made up mainly of rectangular blocks (for entities, or data) linked with relationships. The links between the blocks describe relations between these entities. There are three types of relationships:

  • one-to-one,
  • one-to-many,
  • many-to-many.

For example, "driver drives a car". Here, the entity "driver" relates to the entity "car" by means of a one-to-one relationship "drives". One driver drives one car.

ER Diagram: one-to-one

An example of a one-to-many relationship is a sergeant commanding a team of soldiers. Here the entity "sergeant" relates to a number of entities "soldier" by means of a one-to-many relationship.

ER Diagram: one-to-many

Since the many-to-many relationship does not adequately represent the nature of interaction between entities, it is rarely used in diagrams, or is used in diagrams with little detail.

Entities and relationships can both have attributes. Example: a car from the first example has number; the "drives" relation may have quality attributes describing the quality of driving, or time attributes, saying when exactly the driver was driving the car.

ER Diagram: attributes

ERDs are mainly used to describe database structures, though they might be used as diagrams describing a structure of a company, organization, or some business processes.

ConceptDraw DIAGRAM extended with Entity-Relationship Diagram (ERD) solution from the Software Development Area allows you to draw very complex and detailed ERD. It has a number of libraries with objects used in diagrams, which are included in relevant templates and samples available from ConceptDraw STORE.

Entity-Relationship Diagram (ERD) Solution in ConceptDraw STORE

Example 1. Entity-Relationship Diagram (ERD) Solution in ConceptDraw STORE

In actual practice, ERDs employing the method of P.P. Chen are used most. Choose the Chen ERD template in ConceptDraw STORE. A new document will open along with the library with objects necessary to create a diagram. Drag the vector objects representing entities and relationships, and then just connect them between each other in the required order. Use respective library objects to indicate the types of relationships and their attributes.

Entity-Relationship Diagram (ERD) <br>with ConceptDraw DIAGRAM  *

Example 2. ERD WordPressFile Reference. Chen's Notation

One of advantages of ERD diagram drawn in ConceptDraw DIAGRAM is that when you move entities on the diagram, they stay connected and you don't need to move relationships too.

Apart from building a diagram manually, ConceptDraw has a built-in tool for drawing an ERD automatically, from a database.

Entity Relationship Model Diagram. Crow's Foot Notation

Example 3. Entity Relationship Model Diagram. Crow's Foot Notation

The samples you see on this page were created in ConceptDraw DIAGRAM using the Entity-Relationship Diagram (ERD) Solution and demonstrate some of solution's capabilities and the results you can achieve.

All source documents are vector graphic documents. They are available for reviewing, modifying, or converting to a variety of formats (PDF file, MS PowerPoint, MS Visio, and many other graphic formats) from the ConceptDraw STORE. The Entity-Relationship Diagram (ERD) Solution is available for all ConceptDraw DIAGRAM or later users.





TEN RELATED HOW TO's:

EIGRP. Computer and Network Examples →

The Enhanced Interior Gateway Routing Protocol (EIGRP) is a progressive distance-vector dynamic routing protocol. It was developed by the Cisco Systems and is available as an open standard from 2013. EIGRP is used to help automate routing decisions and configuration of the computer network. It allows the routers of the same logical area automatically share route information.EIGRP. <br>Computer and Network Examples *
Picture: EIGRP. Computer and Network Examples
Related Solution:

DFD Flowchart Symbols →

A Data Flow Diagram (DFD) is a graphical technique which allows effectively model and analyze the information processes and systems. The ability to fast and easy create the DFDs is made possible with Data Flow Diagrams solution from the Software Development area of ConceptDraw Solution Park. For designing the Data Flow Diagrams are used simple DFD flowchart symbols which are connected each other by arrows depicting the data flow from one step to another.DFD Flowchart Symbols *
Picture: DFD Flowchart Symbols
Related Solution:

Accounts Payable Flowchart →

Accounts Payable Flowchart - There is nothing easier than do it in ConceptDraw DIAGRAM. ConceptDraw DIAGRAM diagramming and vector drawing software provides the Accounting Flowcharts Solution from the Finance and Accounting Area of ConceptDraw Solution Park. The Accounting Flowcharts Solution contains templates, samples and library of ready-to-use predesigned vector objects that will help you create: accounts payable flowchart, accounts payable process flow chart, accounting flowchart of any complexity quick and easy.Accounts Payable Flowchart
Picture: Accounts Payable Flowchart
Related Solution:

Fundraising Pyramid →

ConceptDraw Pyramid Diagram software allows drawing column charts using predesigned objects or drawing tool.Fundraising Pyramid *
Picture: Fundraising Pyramid
Related Solutions:

Context Diagram Template →

This template shows the Context Diagram. It was created in ConceptDraw DIAGRAM diagramming and vector drawing software using the Block Diagrams Solution from the “Diagrams” area of ConceptDraw Solution Park. The context diagram graphically identifies the system. external factors, and relations between them. It’s a high level view of the system. The context diagrams are widely used in software engineering and systems engineering for designing the systems that process the information.Context Diagram Template *

Picture: Context Diagram Template
Related Solution:

Components of ER Diagram →

It is easy to recreate any informational system structure using diagrams. There are three main components of any ER diagram: entity, attribute and relationship. Basing on these three components, one can define other, less used elements, such as weak entity or relationship, derived attribute, recursive relationship etc. This is the set of graphic elements of ERD Chen's notation. This ERD notation is used to represent an entity–relationship models. It involves the set of geometric forms: rectangles - depicting entities, ovals - representing attributes and diamonds depicting relationships assigned for first-class objects, that can have relationships and attributes of their own. Connections are displayed with arrowed lines. It is known that the Chen's ERD notation is used to show a detailed view of entities and relationships. ConceptDraw Entity-Relationship Diagram solution from the Software Development section of Solution Park provides the ability to create ERD of database structure for software development purposes using the Chen’s notation elements.Components of ER Diagram *
Picture: Components of ER Diagram
Related Solution:

Entity Relationship Diagram Examples →

ConceptDraw DIAGRAM diagramming and vector drawing software offers the Entity-Relationship Diagram (ERD) Solution from the Software Development Area for ConceptDraw Solution Park. How many examples contains the Entity-Relationship Diagram (ERD) Solution! All Entity Relationship Diagram examples were designed and saved for ConceptDraw DIAGRAM users. Now they are available from ConceptDraw STORE.Entity Relationship Diagram Examples *
Picture: Entity Relationship Diagram Examples
Related Solution:

How to Create a Social Media DFD Flowchart →

In order to be successful, you have to promote your business on the market. One of the ways for planning this promotion is to create a social media DFD Flowchart which will contain all the details of your business strategy. Social media is a very influential tool, and it's a mistake to ignore it. The following flowchart represents a best way to estimate social media posts, and gives a strategy of responses. This flowchart is designed in the format of cross-functional flowchart. With this format, we can divide the process into three distinct phases. This approach helps to generate well-considered and balanced response on social networks activities. Using ConceptDraw solution for Social Media Response, your reaction to social media posts will positively mirror the values and mission of your business.How to Create a Social Media DFD Flowchart *
Picture: How to Create a Social Media DFD Flowchart
Related Solution:

UML Diagram of Parking →

This sample shows the Use Case Diagram of parking lot control system. On this sample you can see use cases represented as ovals and three actors represented as figures of persons that employ these use cases. Associations between actors and use cases are shown as lines. UML Diagram of Parking - This diagram can be used for understanding the process of working the car parking, at the projection and construction the parking by building companies and for automation the existing parkings.UML Diagram of Parking *
Picture: UML Diagram of Parking
Related Solution:
ConceptDraw
DIAGRAM 16