ELECTRONIC DATA
PROCESSING (EDP)
u Need
for EDP
u Examples of EDP
u Effects of introducing computers in
data processing systems
u Stages of computerization
u System flowchart
1
Introduction
u data
processing was possible a long
time before the invention of the
computer, e.g., using
u abacus
- manual data processor
u old-fashioned cash registers - mechanical
u when
an electronic device (computer) is
used to process data, this is called
electronic data processing (EDP)
2
Need for EDP
u Advantages
over other ways as
computer operates
u faster
u more
accurately
u more reliably
u more economically
u Characteristics
of data processing tasks
u How computers can help
3
Characteristics of data processing tasks
u accurate
records must always be maintained
u high
speed processing is required
u large
volumes of records are handled
u calculations
are often routine & repetitious
u much
of the work is very tedious, e.g., sorting
& searching
4
How computers can help?
u accuracy
u provided
that instructions & data are correct
u speed
u consistency
u same
results can be produced with same data,
instructions & process
u storage
capacity
u stored
on various media
u automation
u human
work is not needed during the process
5
Examples of EDP
u Payroll
system
u Mailing list
u Stock control system
u Ticket buying (URBTIX) system
u Point-of-sale system
u Electronic fund transfer
- easy pay system(EPS)
6
Effect of Introducing Computer
Data Processing Systems
u Advantages
u save
time, save money
u save
staff for some routine work
u better
control over an organization
u better
knowledge & better reaction
u better
customer services
7
u Disadvantages
u extra
u staff
cost in employing specialists
may find this unacceptable due to the
changing of working procedures
u extra
cost in equipment, office space &
furniture
8
Criteria for Computerization
u What
is the problem of in the existing
system?
u Can the problem be solved using a
computer
u It is cost-effective?
u Is the use of computers acceptable to
the staff?
9
Stages of Computerization (8)
u preliminary
study
u feasibility study
u system analysis
u systems design
u program design, coding & testing
u systems implementation
u systems maintenance
u systems evaluation
10
u Preliminary
study
u investigates
& identifies the areas
that need to be computerized
u Feasibility
study
u decide
whether computerization is
the best solution to the problem, the
project needed to be process or not
11
u Systems
u the
present system is analysed
u Systems
u the
analysis
design
type of hardware & software
u input
& output format
u storage
method, file structure
u processing
flowcharts
specification & system
12
u Program
u done
design, coding & testing
by programmers
u Systems
Implementation
u changeover
from the existing system
to the new one
u staff training, installation of hardware
& software
u 4 common approaches of changeover:
parallel, direct, phase, & pilot
13
u Systems
maintenance
u the
system is continually modified &
maintained to meet the users’ new
requirements & fix the newly
discovered bugs
u Systems
evaluation
u to
determine whether it is meeting
initial requirements
14
Systems Flowchart
ua
diagram uses symbols & interconnecting
lines to show the data flow & sequence of
operations
u help systems analysts & analyse & design
systems
u symbols: manual operation, merge, manual
input, document/report, punch card,
magnetic tape, magnetic tape, a magnetic
disk, display, communication link & process
box
15