·
Data
redundancy is found- the presence of duplicate data in
multiple data files
e.g. Customer Name, NI number,
Address is present in several different files on several different systems.
Errors are generated, time entering data is wasted.
·
Data
inconsistency will become a problem
e.g. information is duplicated in each system
and may be updated in most systems but not necessarily in all – the savings
account and loan account may have different addresses for a particular
customer.
·
Lack
of data independence.
In the bank imagine cases where any change in data
format or structure requires a change in all the programs that access the data.
e.g. effort required to change from 3-digit STD to
4-digit STD may be very difficult.
·
Data
lacks integrity
This is the
quality by which information from the system can be trusted.
·
Lack
of flexibility
Creating reports
e.g. in this system a
summary of account balances in each separate account would require separate
reports for each open account or cutting and pasting into a word processor file
– not a satisfactory state of affairs.
·
Data
not shareable. Similarly if different departments
want to access data this would be very awkward.
