Designing A Database For BigM: Conceptual Data Model, Relational Database Schema, And Essay.

The proprietors of BigM have approached you and asked if you could design a database to help them manage their business. The management has commissioned you (in your capacity as a Database Management System consultant) to analyse, design and develop an appropriate conceptual data model and relational database schema, based on the following information gathered about the current business activities.

• BigM operates stores in many cities in Australia. Stores are referenced by store number. BigM also keeps store name, phone, fax, email for each store. Each store has a postal address containing street address, city, state and postcode.
• Each store has a number of departments, for example, finance, accounts, sales, customer service etc. For each department, there is a department ID, department name, phone and e-mail addresss.
• Each department has a number of For each employee, BigM keeps a record of their employee ID, first name, last name, phone, date of birth, start date of his/her work and tax file number.
• BigM also stores postal and residential addresses of their For each address they need to store street address, city, state and postcode.
• For each employee, his or her job type (for example, accountant, sales, customer service etc.), and annual salary is recorded.
• Each store is managed by an employee as a store manager and each department is supervised by an employee. The department supervisor is also the supervisor for all the staffs within that department.
• Each store may be assigned a supervising store where all training, payroll, server application and help desk are located.
• Each supervising store generates pay slips for all staffs (in this store and other stores being supervised) on a fortnightly For each pay slip, the store records a pay ID, supervising store ID, employee ID, pay date, number of hours and the gross payment.
• BigM sales different products like CDs, cloths, computers etc. For each product it stores product number, product description, brand, toys, product size and
• An inventory of the number of each particular product in each store is BigM keeps track of the quantity of each product that is on order, as well as the number currently available in each store.
• Customer may place orders in the store. Customer details are always taken at each A customer is referenced by a customer number, customer first & last names, phone number and postal address, if available. For each address they need to store street address, city, state and postcode.
• A customer may order more than one product at a time, and they may order multiple copies of the same product. BigM also records the date a product arrives and the date when it is picked up by the customer. Note that these dates may be different for each product.

BigM understands that they may not have provided you with sufficient information. If you need to make assumptions about their organisation please ensure that you record them.

From the BigM’s business requirements specified above, prepare a document according to the followings:

1. Use the supplied template for your Assignment

2. An appropriate title page that includes an acknowledgement of all students you have spoken to about the assignment. 

3. A table of contents and page

4. An ERD using Crow’s Foot notation. The diagram should include:

a) all entities, attributes, and relationships (including names) ;

b) primary keys (underlined) and foreign keys (italic) identified;

c) cardinality and modality (optional / mandatory) symbols; and

d) assumptions you have made, e.g., how you arrived at the cardinality and/or participation for those not mentioned or clear in the business description,

5. Normalisation of the relations which identifies:

a) dependency diagram for each relation

b) the level of Normalisation achieved for each relation

c) the reasons for any relation that is NOT maintained in

6. Relational database schema that translate your ERD and include:

a) relation (table) names,

b) attribute (column ) names and data types (as required by XAMPP or UwAmp),

c) length of each field & its description (e.g., if it is a primary key, a foreign key referring to another table or format, etc.)

d) primary and foreign keys identified;

7. A bibliography, containing all resources used to complete the assignment. If no resources have been used please indicate this appropriately.

                                                                                                                 (Source: Created by Author)

Assumptions: The customer will make order from the website. A bridge table has been used for tracking the product quantity for each order. The postal and residential address will refer to the same entity. An employee acting as the supervisor of the store will not work in any department. The pay slip will be provided to the employees by supervising store under which they work. The inventory will be used to track the stock the availability of the products. The inventory entity also specifies which store has which products.

1st Normal Form: In order to be in the first normal form, the attributes are required have only atomic values and a primary key for each table. As shown the figure 1 ERD, all the tables have at least one primary key and all the attributes are atomic. Therefore, the database tables are perfectly in first normal form.

2nd Normal Form: The second normal form states that non-key attributes should be depended on key attributes.

In the above table, the street, city, state and postcode are depended on the addressID. Therefore, the table has partial dependency. To remove the partial dependency, the table is divided into two separate tables named customer and address.

3rd Normal Form: The database must be in second normal form and it does not have any transitive dependency among the attributes.

The storeID determines the departmentID detrrmines the departmentName. But the departmentID does determines storeID. Therefore, the table has transitive dependency. To remove the dependency, the table has been separated into two table named store and department.

Al-Masree, H. K. (2015). Extracting Entity Relationship Diagram (ERD) from relational database schema. International Journal of Database Theory and Application, 8(3), 15-26.

Letkowski, J. (2015). Doing database design with MySQL. Journal of Technology Research, 6, 1.