Computer Science – Databases | e-Consult

It is crucial to use a lookup table to validate the 'Grade' field because it ensures data consistency and prevents invalid grades from being entered. Without a lookup table, users could enter arbitrary text, leading to errors in reporting and analysis. A lookup table enforces a predefined set of valid grades.

Example Lookup Table Structure:

Implementation: The application would query the lookup table to check if the entered 'Grade' value exists in the table. If it doesn't, an error message is displayed, prompting the user to enter a valid grade.