06 Jun Entity-Relationship Analysis and Diagram

 

 

 

 

 

 

 

 

 

 

Entity-Relationship Analysis and Diagram

 

 

Entity-Relationship Analysis and Diagram

Entity-Relationship/ER diagrams represent tools that individuals use to exhibit the connection/ relationship between entities in a set of data. A set of entities represents the collection of comparable entities. The ERD/Entity-Relationship Diagram is widely used in organized conceptual modeling and analysis. The ERD is easy to understand, powerful to model different issues, and can be readily interpreted into a database schema. In this instance, the ERD includes a business entity, including different relationships within the organization used to them.

The ERD presented above represents an organization, thus it shows:

• Relationships
• Entities
• Membership Class
• Relationships Degree
• Marked up descriptions for every relationship

 

An entity or entity type refers to a specific type of object. In the real-world scenario, an entity represents a significant organizational object, containing different or more than one property. In the same breath, it is essential to note that a weak entity represents an entity whose existence depends on the owner entity/parent entity, meaning that it is existent dependency. Therefore, the weak entity lacks an individual identifier.

Relationship or relationship type signifies the connection between various entities. One might understand this as the relationship representing a connection that ought to be recollected by the database system. In this instance, one should note that a relationship can be binary, unary, or non-binary, which all depends on if the involved entities in a relationship is one, two, or more than two.

On the other hand, an attribute refers to a property that an individual uses to describe a relationship or entity. Consider that some approaches do not permit for the attribute to be in or have a relationship. A foreign key represents the primary attribute being the key to a different relation.

Cardinality limitation stipulates the sum/number of relationship occasions where an entity can join/share. Cardinality limitations include M:N, 1:N, 1:1, in binary relationships, and  M:N:P, 1:1:N,  1:1:1, and 1:N:M, in ternary relationships. Such constraints resemble the maximum cardinality in different notations.

Finally, a participation specifies if an entity can exist without taking part in a relationship/associating with a different entity. Such a constraint resembles minimum constraints in different notations. Partial or optional and mandatory or total participation represents the two kinds of participation.

Relational Database

The process for normalizing the process changes, the idea behind this is to merely breakdown the presented package/entities into lesser segments. The database compiles the entities and relational diagram, which in return reflects the organization’s basic for position, positional description, including the responsibilities and roles (PMBOK, 2008). In addition, the workload could be more detailed as well in an individual incorporates the responsibilities and roles as exhibited on the initial image within the primary/key segment. Furthermore, the relationships represents the order of operations, including the responsible information flow. Considering that the hierarchy is visualized or can be seen, an entity or the management may want to reflect/deliberate the process’s performance as they can readily established the organizational effectiveness. 

Database Design

Universal Database

Staff attendance scheme/database

Staff Information database

Staff Attendance

 

 

References

 BIBLIOGRAPHY PMBOK. (2008). Project Quality Management. In PMBOK, A Guide to the Project Management Body of Knowledge (PMBOK GUIDE) (pp. 189,192). Newton Square, Pennsylvania: Project Management Institution.