COIT11237 Database Design And Implementation

Assignment

Data Structures

ERD Diagram and Logical Conceptual Design

Solution

The case study is not given in the question. So for this case, we will take the case study from data structures textbook. The overview of case study is shown below: (Kroenke et al., 2018)

CQ Air Conditioning Services (CQAC) plays the set up and maintenance of air conditioning gadgets on their customers’ premises. When a new client requests to be established, CQAC collects its non-public information which includes call, deal with, touch statistics, electronic mail cope with, etc. Putting in cooling units in other homes which include their units / houses or offices, and so forth., consequently, they also gather the touch person and details of the address of the premises where the set up is to take place.

Next, one of the CQAC personnel inspects the houses and offers the client installation options. The current set up alternatives supplied are pulled, established and installed inside the air conditioning window. Once these alternatives are finished via the consumer, a purchase / agreement order is made through them and a replica is supplied to the consumer. Currently 40% of overall expenses are gathered as early price from customers.

After putting in aircon devices through its body of workers, CQAC conducts an inspection go to, resolves problems if any and collects the final set up expenses.

Whenever CQAC receives a restore request from its customers, hassle-associated statistics is to be had and the date of the go to be corrected is notified to them. Upon of entirety of the repair work by way of their personnel, an bill is issued to the patron.

ERD Diagram and Logical Design

The Case study actually says to draw the ERD Diagram and either perform Logical Design or create 3NF Relations. So in this case we will draw ERD Diagram ad perform Logical Design. Before drawing the ERD Diagram and performing the Logical Design, let us get an overview about ERD Diagram.

ER Diagram additionally known as ERD is a diagram displaying the relationships of commercial enterprise units saved on a website. In other words, ER diagrams assist to explain the logical structure of data. ER diagrams are created primarily based on three basic concepts: enterprise, attributes and relationships. ER drawings contain diverse symbols that use rectangles to represent agencies, ovals to describe functions and diamond structures to represent relationships. It is a facts version of a excessive-stage idea. The ER model enables to systematically analyze information desires with the intention to produce a nicely-designed website. The ER Model represents actual-international organizations and relationships among them. Creating an ER Model in DBMS is taken into consideration the first-rate way before the use of your database.

ER Modeling enables you to analyze information wishes systematically if you want to produce a nicely-designed website. Therefore, it is considered the nice practice to complete ER modeling earlier than the usage of your database.

Reasons to use ERD Diagram (Guru99, 2019)

• Helps you outline phrases associated with enterprise dating modeling
• Give a preview of how all your tables have to be connected, which fields can be in every table
• Helps to outline organizations, attributes, relationships
• ER diagrams are translated into related tables that let you fast create records
• ER diagrams can be utilized by internet designers as a statistics utilization plan for specific software program applications
• The database clothier gains a higher knowledge of the facts that have to be contained at the website with the help of ERP diagram
• The ERD Diagram lets in you to hook up with a logical internet site shape for users

The ERD Diagram is shown below:

The ER diagram describes how the consumer locations an order and the way the order is processed with the aid of the corporation. After placing an order with the organization the business enterprise offers a unique order id and symptoms the client agreement and fits the ac in the targeted region as described by using the purchaser by way of supplying the installation alternatives. After making the entire charge invoice is produced through the client. The system for processing ac application is much like the above.

Logical Design

This type of design may be taken into consideration as an summary degree layout in a pc program wherein programmers prepare statistics into a chain of logical relationships referred to as attributes or corporations. Business refers back to the statistics component, even as the characteristic describes the precise functions of the business.

Creation of Logical Designs (Overview of Logical Design, 2019)

It is a idea, an abstract type of design. You aren’t managing details of physical pastime but; it best works by means of defining the sorts of statistics you want.

The rational layout manner entails organizing records into a chain of logical relationships referred to as agencies and attributes. A enterprise represents a positive piece of information. In related databases, a business commonly creates a table map. An characteristic is part of a commercial enterprise and enables outline business variety. In related databases, column map attribute. (Thiru, 2017)

You can create a logical design using pen and paper, or you may use a layout device like Oracle Warehouse Builder or Oracle Designer. Although business relationship drawing is often related to more common models consisting of on-line transaction processing (OLTP) programs, the methodology continues to be useful in modeling size. You just have a look at it in another way. In dimensional simulation, as opposed to trying to find atomic gadgets of information and all the relationships between them, you are trying to identify which table statistics is inside the center proper and which table records is length related.

The most effective output of a logical design is a set of corporations and attributes that correspond to reality tables and tables of significance. Another way to map performance facts out of your source to difficulty-specific statistics on your warehouse facts schema. Identifies enterprise topics or facts fields, explains relationships among enterprise subjects, and specifies attributes for every topic.

Factors that assist you determine the warehouse schema data version in your source data and your consumer needs. In a few instances, you may find a source version to your corporation’s commercial enterprise data version and then re-engineer a logical statistics model on your statistics repository. The real implementation of a logical statistics repository version may also require some modifications due to your gadget parameters – system size, variety of users, storage capacity, network type, and software. So, for this case, the logical design is shown below:

References

ANISAH MOHD SAAD, N., & MUNIANDI, M. (2020). The Reflections on the using of Oracle Data Modeler in Creating Entity Relationship Diagram (ERD). International Journal of Research Publications, 66(1). https://doi.org/10.47119/ijrp1006611220201601

Guru99. (2019, May 10). ER Diagram Tutorial in DBMS (with Example). Guru99.com. https://www.guru99.com/er-diagram-tutorial-dbms.html

Kroenke, D. M., Auer, D. J., Vandenberg, S. L., & Yoder, R. C. (2018). Database processing : fundamentals, design, and implementation. Pearson.

Overview of Logical Design. (2019). Oracle.com. https://docs.oracle.com/cd/A87860_01/doc/server.817/a76994/logical.htm

Thiru. (2017). Logical Design. Myreadingroom.co.in. http://www.myreadingroom.co.in/notes-and-studymaterial/65-dbms/508-logical-design.html