We already know the saying“Garbage in = Garbage out”

We know that bad data entering a system can have strange results on the data leaving the system after it is processed…

We need to make sure data is accurate so that useful information can be produced.

We also need to make sure that information is passed on within a given period of time to ensure it remains useful.

Air traffic controllers need to know where all planes are at all times.

In order for them to put their planes into a formation around the airport they need to have real time information.

If they receive information about the position of a plane with a delay time of 30 seconds they may instruct a pilot to fly into a location they believe is available…but it isn’t…that would be bad.

Explain why it would be important for a student to receive his grades on time and not a week later.

Explain why it is important that a take away Chinese restaurant needs to ensure that a placed order is correct.

We have already covered accuracy of information back in AS…3.1.1.

We can use validation and verification checks to ensure data is accurate.

These ensure data meets certain criteria.

For example:› Range checks ensure values are entered within a

certain range.› Input masks ensure we enter data in the correct

format.› Type checks ensure we enter the correct data types.

For more examples, look at the 3.1.1 presentation called validation and verification.

These ensure we have entered what we meant to enter.

For example, a double entry check will ask us to type in something twice…

This makes sure we have typed it in correctly and as we expected.

When you are asked to change your password you are often asked to perform a double entry verification check.

Real time systems require that we process and output a response within 4 seconds.

An online booking system needs to update ticket sales in real time to avoid double booking.

Air traffic controllers need real time systems in place to ensure accuracy.

Some organisations do not require real time systems…but they still need to pass on information to other people swiftly.

Rules have to be in place to ensure information is passed on quickly.

In the Chinese restaurant, the telephone operator must pass on the order to the chefs before they take another call.› This will ensure orders to not back up and

means customers will get their orders quickly.

Describe one consequence of share prices being inaccurate on trading days.

A person uses an ATM and checks their balance. They are surprised to find more money than they expected…especially considering they spent a lot of money the previous day. They take out more money but then later find out that they have gone over drawn. Why might this be?

Identify three methods to ensure data is transferred accurately and speedily.