3.SCHOLARSHIP (ScholarshipNo, ScholarshipName, DonorName) STUDENT (StudentID, StudentName, ProgrammeCode) AWARD (ScholarshipNo, StudentID, AwardAmount, AwardDate) (1) Describe how the Entity Integrity rule can be enforced in the STUDENT relation.[3 marks] As StudentID is the primary key of the STUDENT relation, a tuple with null for the StudentID attribute should not be inserted for the STUDENT relation, and value of StudentID should not be repeated. (ii) Describe how the Referential Integrity rule can be enforced in the AWARD relation. [6 marks] As AWARD.StudentID is a foreign key targeting the STUDENT.StudentID, AWARD.StudentID must either match an existing value of STUDENT.StudentID, or it must be wholly null. It is not possible to create an AWARD tuple with StudentID "11110879", unless there is already a record for StudentID "11110879" in STUDENT relation. 4. With the help of a diagram, describe the ANSI-SPARC Three-level Architecture. [14 marks] For ANSI-SPARC Three-level Architecture, it includes external level, conceptual level, internal level. External level is the users' view of the database, describes that part of database that is relevant to a particular user. Conceptual level is community view of the database, describes what data is stored in database and relationships among the data. Internal level is physical representation of the database on the computer, describes how the data is stored in the database. External level EXTERNAL SCHEMA Conceptual level Logical Data Independence CONCEPTUAL SCHEMA Physical Data Independence Internal level INTERNAL SCHEMA Physical level Database