All businesses strive to make profit out of their products or services. To cover costs and expenses without having a deficit, businesses need to plan well and make safe decisions to make sure that every step of progress is right and well organized. Drawing an entity relationship is one way businesses design their data storage, data input and output, and other processes in a system. Designed be Peter, entity relationship diagrams are included in a conceptual level where its features are almost similar to those of Relational diagrams. Entity relationship diagrams come with a form of graphical figures which can be right for some processes and systems. As its name indicates, E-R diagrams show representations of information and data where its components: entity, attribute, and relationship, as follows, will represent a more complex relationship or interactions between components or data. Relationships include: one to one, one to many, and many to many.
In order to create an efficient ERD, technological tools and well developed software will be needed. There are many tools available for generating entity relationship diagrams; most of the tools are computer based and some are software. Many of software available in the internet for free, can generate ER diagrams and interpret models professionally. Some programs and software can also interpret SQL and do extra data base analysis, which will make things a lot better and saves time for businesses. To generate SQL simply, the drawing shapes along with line and tools given in software will generate real figures that hold meanings in them. It is essential and needed to know what each symbol means or else software or programs won’t help either.
Limitations to Entity Relationship Diagrams
ER models only assume that information given and recorded in the system is ready to be transported and represented in a relational database. ER diagrams only describe and explain relational structure for this information. Semi-structured data or information that is not ready to be presented in a relational database in not included in the entity relationship diagram. Changes in information within the diagram are difficult and indeed complex to make. In order to make further changes, the author must extend the diagram and add constructions to the diagram itself, making information input and output confusing. A solution to this problem is to use process modeling technique so that changes can be modeled separately from the diagram. ERD only aims and focuses at specific information which can be beneficial for new, independent information systems. However, for existing information sources that have defined their own data, it wouldn’t be a great idea and will be less of a help of businesses, making things more complex. ER diagrams are not commonly used for a separate activity; due to new developments and technology, there are numbers of software and new diagrams that are similarly close to ERDs with more benefits and simplicity.
ERD is indeed an excellent tool to manage business performances and ensure the flow of private information, both output and input. It is one of the most common tools in communication which can be used to confirm business decisions and requirements as well as provide vision to move and push the design and architecture team forward with success. Looking deeply into business rules, entity relationship diagrams will help a lot in determining which information is needed to be kept or eliminated. In order to ensure safety and make the right decisions, models or ERDs are needed to picture out the whole business plan. For instance, a project is to build a data warehouse. With an ERD, businesses can picture out how things will be like and will be able to calculate and evaluate results of each alternatives or ideas before making real decisions or giving out final answers. However, if a project requires extracting data from one source to another without storing it in a data warehouse or mart, then an ERD will no longer be needed.
Pros and Cons of Entity Relationship Diagrams
The main advantages of an ERD are conceptual simplicity or the convenience in using the diagram in presentations; visual representation on projectors makes it easier for programmers to present and interact with other employees or workers; ERD’s effective communication system through figures, arrows, and shapes enhance great understanding and efficiency. ERD has several disadvantages but not as much as its benefits and advantages. It has limitations such as: limited constraint representation, limited relationship representation, no representation of data manipulation, and loss of information. Though ERDs are used to show relationships between entities and components, its limitations on information representation also prevents its uses for some projects.