Question $5$

$[20]$

Scenario: Even now, in $2024,$ individuals' use of banking apps to carry out transactions is on an exponential rise worldwide. This is true in other sectors of e$-$commerce. Nowadays, many commercial banks have Apps that allow their customer to undertake a number of transactions using their mobile devices. For this to be possible, each bank keeps a database at the back end that the Apps can access. Such a database can be very complex in terms of its design. In this question, we shall focus on a small section of this type of database.

Each customer, normally called a client, can have more than one account, such as savings, cheques, etc. Before any transaction is made, a customer must always decide on the transaction type, such as a withdrawal, deposit, etc. The selected type can be done on different accounts, and each account can have several transaction types. In each country, there are usually many banks, and each bank has its own App. The database required in this scenario will be for only one such bank.

$5\mathrm{.}1$ Draw an entity relationship diagram $($ERD$)$ for this banking system. The ERD should not contain any many$-$to$-$many relationships. No attributes$/$fields are required in this section. $($use a Crow's foot notation since it is clearer and more popular than other notations$)$

$(10)$

$5\mathrm{.}2$ Create a relational database schema from the ERD showing all tables in $3$NF$.$ Each table should include at least three fields$/$attributes$.$ Appropriate primary keys should be used. Primary keys must be underlined, and each foreign key should have the letters FK in brackets after it$,$ for instance, xyz $($FK$).$ You may also use PK to indicate a primary key.

$(10)$