Slides in this set
There are many different types of data; logical or
Boolean, alphanumeric or text, numeric, real
numbers and integer, and date are the ones we
need to know about.
We need to be able to match them up to data in
the exam or give the definition of each.…read more
Boolean or logical data (I'm going to call it
Boolean) holds one of two values for example:
Male or Female, Yes or No, True or False.
Boolean data types are used to answer questions
where there are exactly two options, three
options would mean it is no longer Boolean data.…read more
A text data can hold any letter, number symbol or punctuation mark.
Otherwise referred to as alphanumeric or string.
It can be pure text or a combination of text, numbers and symbols.
E.g. Name Jade Green, Car Registration EM93 DPL
And unexpectedly telephone numbers.
People assume that phone numbers would be an integer data type
but if you think about it you will realise that nobody really wants to
count up and calculate phone numbers. Plus if it was an integer it
wouldn't be stored with a zero on the front because it would be
discounted. That is why they are stored as text or string data types.…read more
These are data types that contain numbers (I'm sure you already knew that
E.g. Measurements, Temperature
When you choose a numeric data type you have the option of making it
more specific :
E.g. Integers these are whole numbers either positive or negative but they
can't be stored with a decimal place.
Real this is used when your numerical data needs decimal places
Currency this is used, obviously, when you need to store money (e.g.
prices). It automatically gives you two decimal places, but you can choose
otherwise in circumstances where the pence is not needed. It also allows you
to display the right currency symbol.…read more
These again are quite obvious they are used to
The difficult thing about these types of data is
that some countries have a different way of
E.g. 9/4/94 means 4th September 1994 in the
USA but 9/4/94 is 9th April 1994 in the UK…read more