Using the Entity Relationship Diagram you have drawn on your piece of paper for the Final Subjects Results Table answer the following question.

Which answer below shows the Normalised Relational Model of the Final Subjects Results Table.

Question

Using the Entity Relationship Diagram you have drawn  on your piece of paper for the Final Subjects Results Table answer the following question.

Which answer below shows the Normalised Relational Model of the Final Subjects Results Table.

BlackTom AI · Accepted Answer

To approach this question, I start by identifying the key entities and their relationships implied by the Final Subjects Results data: students, subjects, lecturers, and the results of students taking subjects, along with marking information.
Option 1: The tables shown place Mark and Grade inside the Subjects table (Subjects (Subnum, Subname, Mark, Grade)) and keep Results only with Stnum, Subnum, CompleteDt. This is problematic because marks/grades are results of a student’s submission, not intrinsic to the subject itself. Storing Mark in Subjects violates normalization by mixing a per-student result with a subject definition. Additionally, Lecturer details are split into a minimal set (Lecturers with Lecturer and LecEmail), which loses the direct relationship between a lecturer and the subjects they teach, and Grades is separated from Mark without a clear dependency explanation. Overall, this design incorrectly distributes per-student performance data and weakens the subject-teacher linkage.
Option 2: This option places Mark and CompleteDt in the Results table but moves Grade into the same row, and it expands Subjects to include Stname and StAddress, which are student attributes. Bringing Stname and StAddress into Subjects couples subject data with student data, causing redundancy and update anomalies if a student’s address changes. Furthermore, the separation of Grade from Mark without a dedicated mapping table for grade rules is questionable, and the Subject attributes no longer reflect only subject details. The result is a design that both mixes student data into Subject and lacks a clean, scalable relationship for grades.
Option 3: This option separates the results into a Results table with Stnum, Subnum, CompleteDt, and Mark, then defines Subjects with Subnum, Subname, and Lecturer* to indicate which lecturer teaches a subject, followed by a Lecturers table with Lecturer, Faculty, LecEmail, LecOffice, plus a Grades table with Mark and Grade, and a Students table with Stnum, StName, StAddress. This structure aligns with normalization principles: per-student-per-subject outcomes live in Results; subject details stay in Subjects; lecturer information is in its own table; and a separate Grades table models the mapping from a numeric Mark to a letter Grade. It avoids duplicating student attributes in subject or results tables and preserves clear foreign-key relationships between students, subjects, and lecturers. The use of a dedicated Grade table to interpret Mark values is a standard practice when grading scales are defined separately from scores.
Option 4: This layout includes comprehensive student attributes (StName, StAddress) in the Results table (Results (Stnum, Subnum, StName, StAddress, CompleteDt, Mark, Grade)), which reintroduces redundancy of student details into the results, violating normalization. The Subjects table only has Subnum and Subname, which is acceptable, but the presence of StName and StAddress in Results compromises update efficiency if a student moves or updates their name. The Lecturers table exists with full attributes, but overall this design keeps dependent student information in the wrong place, leading to potential anomalies and inconsistent updates across the schema.
In sum, Option 3 best reflects a normalized relational model by properly separating per-student results from subject and lecturer definitions, while also modeling the relationship between marks and grades without duplicating student data in subject or results records. The other options tend to misplace attributes (student details inside subject or results tables) or mix per-student performance with subject definitions, which are signs of poor normalization.

Using the Entity Relationship Diagram you have drawn on your piece of paper for the Final Subjects Results Table answer the following question. Which answer below shows the Normalised Relational Model of the Final Subjects Results Table.

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