Database Flashcards
Database
Consists of more than one table
Table
Consists of more than one record
A key
Uniquely identifies records in a table
Data verification
Checking data is input correctly
Example of data verification
Proof reading
Data validation what it does
Checks data is reasonable, sensible and within acceptable limits and if data present and correct type
If the data validation displays an error message
The data has been rejected
Five validation checks
Presence Check
Length check
Type check
Format check
Range check
Presence check
Ensures data is present and can’t be left blank or null
Length check
Correct number of characters
Type check
Check that all data is entered in the correct data type
Example of length check
Phone number
Type check example
Numeric, text and data
Type check example
Numeric, text and data
Format check
Data entered matches a predetermined pattern
Format check example
Postcode
Range check
Data is entered within a lower and upper limit
<
Less than
<=
Less than or equal to
>
Greater than