virtual university of pakistan

Your assignment must be uploaded before or on Tuesday 27^th Nov 2012.

It should be clear that your assignment will not get any credit if:

The assignment is submitted after due date

The assignment is copied

           

The objectives of this assignment are,

Giving the idea of a most commonly used semantic data model for graphical representation of conceptual database design i.e. Entity Relationship Data model. 

Giving the idea of entities and their attributes and the relationship between them.

Providing an understanding of types of relationships i.e. in how many ways an entity interact with other entity in real world.

This Assignment is the continuation of First Assignment. Take same case study given in Assignment 1 (also provided at the end of this assignment), apply the techniques and methods given in lectures and by utilizing the solution of first assignment uploaded on LMS in the form of DFD in order to finalize the tasks of second assignment listed below in task description.  Some hints are provided below to link DFD with ERD which can be helpful in your design process.

Hints:

Every data store in DFD must correspond to at least one entity in the ERD.

There should be processes in DFD which create, modify and delete instances of the entities in the ERD.

For every relationship in ERD there should be a process in DFD which uses it.

In this assignment you will focus on the tasks given below:

You have to identify as many Entities as you can for this system.

You have to find out all possible Attributes of these Entities.

You will have to find the Relationship among those Entities.

Identify all the cardinalities existing between the entities and also show their dependencies.

You will make a final comprehensive ER-diagram consisting of all Entities, Attributes and their relationships along with their respective Primary Keys.

You have to perform all these steps given above in your solution file.

Note:

Use all concepts you have studied so far and techniques in order to identify Entities, attributes and their relationships of the given case study discussed particularly from 7 to 14 regarding ER data model.

Drawing Final ER Data Model:

You can use any tool for drawing like MS Office or Visio.

Important things to consider: 

As happens in real world that everyone visualize a problem in different way so the solutions of all students should be according to their own thinking not taken from some source.

As this is your first comprehensive design, so you have to work very keenly and with concentration. This design requires your full attention as this conceptual design will be transformed into a relational model in next assignment. Any mistake in this conceptual design can cause you much burden afterwards.

Case Study

In this course we are going to develop a complete physical database for “Trade Management System” that will computerize all the necessary Trade Management processes for a small business shop, BEST Mart. For this we will divide this whole project in small 4 to 5 assignment chunks and will try to cover every phase of database development life cycle from scratch to execution. Scenario for the Trade Management System is given below.

There exists a BEST Mart- a shopping centre, whose owner wants to computerize his business by developing Trade Management System. For this, owner hires a Database Administrator and put up a real world scenario and requirements as given below:

Trade Management System permits users to proficiently initiate and evaluate the process of requirement for the BEST Mart. Procedure begins when a client comes to BEST Mart, selects the cart and place the things in cart and goes towards salesman. The salesman examines the code of each selected item. On entry system will display invoice with some details like name of the product, its related magnitude/quantity and total sales line items along with total bill. After placing order, client will ahead to accountant counter to pay bill. 

Trade Management System will support both types of customers, Registered and Non-Register. For Registered customers it is necessary for system to check whether he/she is on credit bases or not. For non-registered customers, it must have to be registered only by the Owner of the BEST Mart. Information about number of creditors and debtors are known by the accounts department.

System will show flexibility in a sense that it should accept all payment methods i.e. cash, credit and cash with credit.

Same is the scenario with Administrator/Owner of BEST Mart to purchase items from different vendors on cash, credit or combination of two. The stock department and Sale department will need to generate reports about stock status sale in different time span.