Systems Analysis and Design

Entity Life Histories

Seq

uenc

e

ELH

DFD LDS

Function Structure

System Data

(SSADM) Data Views

Entity Name

Event A Event B Event C

Sequence

New Staff Recruited

New Trainee Accepted

New Employee

Event D Event E

Employee

Selection

New Employee

Employee Life

Event E

Employee

Iteration

Salary Payment

Bank Account

Account Opened

Account Life

Account Closure

Account Deletion

Transaction

Pay Deposit

Direct Deposit

Cheque Cashed

Bank Account Entity

New Staff Recruited

New Employee

Main Life Possible Ends

Employee

Employee Entity

New Trainee Accepted

Salary Payment

Employee Resigns

Employee Fired

Entity

Birth Event

Account Life

Account Closure

Account Deletion

-/1 1/2 2/3 3/4

State Indicators

State Indicator Format:

valid previous values/value set by event

Bank Account

Account Opened

Account Life

Account Closure

Account Deletion

Transaction

Pay Deposit

Direct Deposit

Cheque Cashed

Bank Account Entity

-/1

1,2,3,4/2 1,2,3,4/3 1,2,3,4/4

1,2,3,4/5 5/-

Bank Account

Account Opened

Account Life

Account Closure

Account Deletion

Transaction

Pay Deposit

Direct Deposit

Cheque Cashed

Bank Account Entity

-/1

1,2,3,4/2 1,2,3,4/3 1,2,3,4/4

1,2,3,4/5 5/-1

5 6

2 3 4

Operations List

1. Create record with account details

2. Add transaction amount to current balance – code a

3. Add transaction amount to current balance – code b

4. Subtract transaction amount from current balance

5. Replace account status by ‘N’

6. Delete account record

Following the opening of a bank account, a number of transactions may occur. These can be a deposit over the counter, a transfer from anotheraccount or a cheque withdrawal. The account must be closed before it can be deleted.

Draw an entity life history (ELH) diagram to reflect the above sequence of events. Include status indicators and an operations list.

Order > 12 months old

Order Received

Payment Received

Goods Despatched

Order

Customer

Invoice

Payment

etc …

etc …

Create Delete Modify

Modify

Create

Create

ENTITY – EVENT MATRIX