02 Introduction

Introduction

Data Validation

• Process of which the data entered is **sensible **and reasonable

Type	Method	Example
Range Check	Check that data is within given range	Test score must be between 0 and 100
Format Check	Check that data is in the right format	Date must be in the format dd/mm/yyyy
Length Check	Check that data length is correct	Length of password must be more than 6 characters
Presence Check	Check that data exists	Username cannot be blank
Digit Check	Check for validity of data	NRIC must be valid

Data Verification

• Process of which to **ensure **the input data **matches **the original resource
• The user may still make a mistake when inputting data
• For example, we are often asked to enter the password twice to change it