Coursework on Database Design and Implementation for Businesses

Learning Outcomes and Tasks

The learning outcomes that are assessed by this coursework are:

1.Select and analyse a problem domain so as to identify data requirements in businesses.

Design and implement a database system for the identified requirements using database modelling techniques and appropriate data description and manipulation languages

Tasks to be undertaken:

You are to develop a database design (both conceptual and logical) for an appropriate business situation of your choice, and then implement and subsequently query an ORACLE database that is derived from your database design.  For this assignment you must work individually. There are two stages to the work you need to undertake: each stage is worth 50% of the assessment mark.

Stage 1 (Scenario and Conceptual Database Design):

Task 1.1: Selection of the case upon which the database design and implementation is to be based

You need to identify a suitable case study from which to derive your database requirements. This may be a situation based on a company with which you are familiar or in which you are (or have been) employed, or may be one (or based on one) that you have read about within the trade or academic literature or identified from their web presence. You need to ensure that your business situation is suitably complex to provide you with at least four strong entities, and at least one specialisation: generalisation structure, yet suitably scoped so as to not require a huge quantity of resultant tables (i.e., normally no more than 15) and subsequent input of sample data for querying purposes. It must not be based on a library (video, book, CD or film) and not just solely about orders of products. It should not be one that is based on any previous examination scenarios for this module, nor any exercises given to you within your DS&D module lecture material and/or module pack. Once researched and identified, a written scenario needs to be produced that (a) provides relevant background information on the organisation (e.g., its purpose, its principal operations/structure, its products/services, its target markets, etc.), and (b) provides an overview of what operations a database would need to support. Your scenario will probably be no less than one side of A4, but no longer than three slides of A4.
You should aim to complete this task by the end of Week 6.

Task 1.2: Provide a conceptual database design for your scenario & the list of enterprise rules being modelled.

Stage 1: Scenario and Conceptual Database Design

The second task is to develop an EER Diagram that captures the detailed requirements for the database system that you identified within the scenario you wrote to satisfy Task 1.1.  The EER Diagram needs to show any weak and strong entities, the primary keys for strong entities, and any relationships between entities (including any generalisation: specialisation structures). *:* relationships must be decomposed, and any actual traps identified should be eliminated using appropriate methods. For each entity, there should be an associated written list of all the attributes that the entity possesses which are not written on the EER Diagram. Any assumptions made during conceptual database design (i.e., anything that you assume that is not written in your Task 1.1 scenario) should be listed.

As well as the conceptual database design, you also need to provide the exact list of enterprise rules that your EER Diagram is diagrammatically representing. (Every relationship will need at least one enterprise rule, depending on its multiplicity and degree. Each binary relationship will typically have two enterprise rules associated with it, for instance.)
You should aim to complete this task by the end of Week 10.

Stage 2:  Logical Database Design and Oracle SQL Implementation/querying

Task 2.1: Provide a Logical Database Design for your scenario

From your conceptual database design, derive a corresponding set of well-normalised tables.  Remember to indicate all primary and foreign key fields for each of the tables using suitable and consistent notation. All key and any non-key attributes should be listed within each table.

Task 2.2: Create the tables using Oracle DBMS

You need to create all the tables that you identified within your logical database design. Make sure the appropriate fields are defined as key, and that other suitable data integrity rules are enforced. Each of your tables should contain your user name as part of the table name. E.g. if your user name is ‘mit10sf’, then if you needed a Car table then you would create a table ‘mit10sfCar’. (Hint: make sure you create the tables in an appropriate order – for instance, those that have foreign keys cannot be created first – why? Think about it!).

Task 2.3: Create the four most useful indexes on your tables

You need to create a total of FOUR appropriate indexes on the tables using the CREATE [UNIQUE] INDEX statement. (Hint: it may be useful to consider what queries you wish to perform in Task 2.5 first, and don’t forget that primary keys don’t need any user-defined indexes as these are provided automatically by Oracle). Write a short explanation as to why you decided to create each index.

Task 1.1: Selection of the Case Study

Task 2.4: Data Population

Populate your Oracle tables with some fictitious yet appropriate test data (about FIVE records per large table and TEN records per small table (or as many rows as is relevant) should be enough).

Task 2.5: SQL Query writing

Define and run SIX queries of your choice (but appropriate to the scenario). Each query should require TWO or more of the following querying facilities, (and all of these facilities should be used at least once in your set of queries) and should be properly justified as to why the query would be useful to your case study organisation:
o  Selection of particular table columns
o  Inner Join of at least 2 tables
o  Outer Join of at least 2 tables
o Use of count and/or another similar mathematical expression
o Use of a sorting/ordering facility
o  A condition using “<”, “>”, LIKE etc.
o  A condition using IN, NOT NULL, or similar.
o  A sub-query

Deliverables to be submitted for assessment:

The results of the above Tasks 1.1 to 2.5 need to be submitted, i.e.:
• Your case scenario, the list of enterprise rules being represented within your EER Diagram, and the whole conceptual database design.
• The logical database design that follows from your conceptual database design.
• A print out of each of the tables (i.e., the extension of each table) that you have created in ORACLE and the SQL code required to create them (including the code for the integrity rules).
• A print out of the SQL code required in order to create the four indexes. You should provide a short written section justifying your choice of indexes.
• A print out of each of the six queries you devised, showing both the SQL query statement and the query result. You should provide a brief explanation of what you expect each query to achieve and why you think this query is relevant to your case scenario.

ONE electronic copy containing all of the above aspects must be submitted for summative assessment via Blackboard’s Turnitin.  ONE copy of each of the Stage 1 & 2 Marksheets, completed with your assessment self-evaluations on the criteria listed, should also be submitted with your electronic copy work. You are permitted to attach a small amount of additional and appropriate evidence to support one or more of your claims, should this be necessary.

Sometime after submission, you may be asked to attend a viva lasting for up to 15 minutes with one or more tutors. You may be selected for a viva for a variety of reasons; for instance, to verify that the work you have submitted is understood/written by you, to clarify aspects of the work to aid marking or just because you were randomly selected. Your mark may go up or down as a result of a viva.  Failure to attend a viva, if you have been asked to do so, may result in you obtaining zero marks for the entire assessment.