Uploaded by Rupert sakyi

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The year 2020 will go down in history as a very extraordinary year in the 21 st century, as
COVID-19 is causing havoc around the world. Due to the COVID-19 Pandemic, most
economies are expected to slowdown and other even expected to go into an economic
recession. These extraordinary times has forced many Small and Medium (SMEs) size
Companies to either temporarily or permanently close down.
In anticipation of a chaotic aftermath, most governments are looking at stimulus packages
for these business. The Government of Ghana for instance has setup a COVID-19 fund
and has since been receiving donations from private organizations and individuals for
such purposes. Even though the unknown is great, one thing most experts seem to agree
on is that these interventions will not be enough if COVID-19 and its accompanying
lockdown drags on until the end of the year. This calls for innovative ideas.
One of such is the Mini-Loans Scheme system proposed by Ghampo Consultium Ghana
(GCG). The idea is to bring borrowers (SMEs) and Lenders (rich individuals, venture
lenders, Micro finance institutions, etc) together at the end of the lockdown, using
information technology. Unlike traditional loans, the money in a Mini-Loan can come from
multiple lenders. Typically, the loans will be used to finance operations of the borrower’s
company, so that there is a realistic chance for repayment. The following information form
the basis for creating their system:
 Each borrower and lender must be registered with information about name and
address.
 A loan starts with a loan request, which contains information about when the
loan should at latest be granted, The total amount being discussed (in Ghana
Cedis), and duration of repayment. Also, a description is included of how the
money will be used. The interest on the Mini-Loan is calculated on the loan
amount.
 Lenders can commit to an optional portion of the total amount of a loan request.
Meaning a lender can commit to grant 10%, 25%, or even 100% of the miniLoan amount.
 When the commitments for the loan request covers the requested amount, the
request is converted to a mini-Loan. If not enough commitments can be
reached, the loan request is cancelled.
 A borrower can have more than one mini-Loan request, and more than one
mini-Loan at a time, but can at most make one request per day.
 The mini-Loan will be paid through an “intermediary”, typically a local
department of a charity, who has a name and an address.
 The borrower chooses when he or she will make a payment. Every payment
must be registered in the database with an amount and a date (at most one
payment per loan per day). The lenders share the repayment based on the
proportion of contribution to the loan. If a lender committed to 60% of the load,
then he/she will get 60% of each repayment amount.
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If the mini-Loan is not repaid before the agreed upon deadline, a new date will
be agreed. The database must not delete the old deadline, but save the history
(the deadline can be overridden multiple times).
Each lender can for each burrower save a “Rating / Trust”, which is a number
between 0 and 100 that determines the lender’s evaluation of the risk of lending
money to that person.
A lender must only be able to rate a borrow he/she has previously lend money
to.
REQUIREMENTS:
(i) Using an appropriate CASE tool (e.g. Erwin data modeler or Microsoft Visio) create
an Entity Relationship Diagram for GCG specifying the key attributes of each entity
type, and the structural constraints on each relationship type. (You may note any
unspecified requirements from the scenario, and make appropriate assumptions
to make the specification complete)
(ii) Discuss the integrity rules in your data model and demonstrate how these were
applied in your ERD.
(iii)Even though the initial plan is for GCG to start in Ghana, plans are underway to
establish branches across the West African sub region. In line with the above GCG
has plans to create a single database system for all branches across the sub
region. To achieve this, GCG will look at the possibility of creating a distributed
database (DDB), since it will further improve the overall performance of the system.
For the purpose of this DDB, GCG will have computer sites located at each of each
of the capital cities in West Africa. At each of these sites, we expect frequent
access to the Lenders, borrowers, and mini-Loans information within that region.
The Site at the head office in Accra will house a copy of the complete database
and accesses all information. Using a modeling technique of your choice, create a
model of fragments to be replicated at each site. You may introduce additional
relations, if necessary.
As a database systems developer, you are appointed by your company to lead the team
of developers that will transform the database schemas designed in coursework 1 above
into a working database system. Write a 10-page proposal (at least 5000 words) to your
boss in the form of an academic paper highlighting the following:
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Justify your choice of a DBMS that is most suitable for the implementation of the
above distributed database system of GCG; including information about vendor,
versioning history, market share, functionality, advantages, disadvantages, basis
for your choice, etc.
Discuss how you intend to ensure the effective administration of the proposed
distributed database, in performing tasks such as End-user support, Data security,
privacy, integrity, Data backup, recovery, etc.
Justify your choice of concurrency technique to ensure the noninterference or
isolation property of concurrently executing transactions for the proposed
distributed database system.
Your analysis and justifications must be within the context of GCG and your
selected DBMS
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