DATA VALIDATION

DATA VALIDATION

What is data validation

Data validation rules are guidelines that ensure data entered into a database is accurate, complete, and follows specific formats. When data doesn't adhere to these rules, it's rejected, and an error message is displayed. This message informs the user about the issue and guides them in correcting the error.

Types of Validation Checks

Presence Check:

• Ensures that essential data items are not omitted.

• Example: In a booking system, all fields like student name, instrument, and session date must be filled.

Types of Validation Checks

Length Check:

• Ensures that data items have the correct number of characters.

• Example: Student and tutor initials might be limited to one character each.

Types of Validation Checks

Range Check:

• Ensures that data values fall within a specified range.

• Example: Student grades might be limited to a range of 1-8.

Types of Validation Checks

Format Check:

• Ensures that data conforms to a specific format.

• Example: A student's surname might be required to start with an uppercase letter followed by lowercase letters.

Types of Validation Checks

Type Check:

• Ensures that data matches the expected data type.

• Example: Fees should be entered as currency values