Testing Information systems

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Testing Information systems

OBJECTIVES

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• To ensure the entire system will perform as per specification

• Ensure system meets users requirements

• Verify if controls function as intended

• To make sure incorrect inputs, incorrect processing and incorrect outputs (if any) will be detected during operation

• Should include both computer based and manual processes

Remember that system testing is done before a system is released as ready for operation

CLASIFICATION OF SYSTEM TESTS

•PROGRAM TESTS

-Program tests with test data

- Normally individual modules tested then integration test done

- Test boundary conditions

- Test using loop counts

•SYSTEM TESTS

-Results from a program fed as input to a succeeding program

- a string of programs run one after another

-All programs in a complete system are tested together as a whole. Tested using unreasonable data and non key data besides normal test data for whole system

• PILOT TESTS

-Use data from manual system to test system when it is first implemented. If it is modification of earlier computer based system use data and output

from that system

• PARALLEL RUNS

-Run both manual and computer based systems with same live data and see if both give identical results

-If it is re-engineered (i.e.,Modified) system run both old and new systems and compare results

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