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Mind Map on Data Handling, created by wmatthew on 04/20/2014.
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Created by wmatthew
over 5 years ago
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Data
Handling
1 Data Validation: Checks that
data entered is reasonable
but cannot check it is correct.
1.1 Range check: It checks the length of the
data entered is within a certain range.
1.2 Presence check: Makes sure data
has been entered in a cell.
1.3 Format check: Makes sure data
has been entered in the correct
format e.g. date of birth.
1.4 Length check: It checks
the data isn't to short or
long.
1.5 Check Digit: It puts digits into a
calculation to check they are valid
commonly used on barcodes.
1.6 Lookup Check: It checks
the data is correct from a
table stored else where.
2 Data Types
2.1 Text: stores both
letters and numbers.
2.2 Integer: Stores whole
numbers that don't begin
with zero.
2.3 Real Number: Stores only
decimal numbers however
they cant start with zero.
2.4 Date: Is used to store date in the correct format
however their is a format choice. Short date e.g.
03/09/2020 or long date e.g. 3rd September 2020
2.5 Boolean: offers a choice of
one or the other. Yes/no.
2.6 List: Offers a few select items
on a list reducing mistake.
3 Databases
3.1 Relational database
3.1.1 It links several tables together
saving on data duplication saving
on mistakes but also time
3.1.2 Can be used to enforce
rules by brining up error
messages when certain
rules are broken.
3.1.3 Easy to run a query.
3.2 Flat file database
3.2.1 One large database holding all the
information means some data may be
keyed twice
3.2.2 Difficult to read and use
day to day
3.2.3 Difficult to run a query on a large table.
3.2.4 More prone to mistakes due to confusing layout.