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Linking students to the branch they are in. Student table rollno* name branch hod office_tel 401 Akon CSE Mr. X 53337 402 Bkon CSE Mr. X 53337 403 Ckon CSE Mr. X 53337 404 Dkon CSE Mr. X 53337 hod and office_tel do no depend on the student, only the branch. Student table rollno* name branch@ 401 Akon CSE 402 Bkon CSE 403 Ckon CSE 404 Dkon CSE Branch table branch* hod office_tel CSE Mr. X 53337 Adding an ID to branch Student table rollno* name branchId@ 401 Akon 1 402 Bkon 1 403 Ckon 1 404 Dkon 1 Branch table branchId* branchName^ hod office_tel 1 CSE Mr. X 53337 1NF student_subject table roll_no name subject 101 Akon OS, CN 103 Ckon Java 102 Bkon C, C++, CN Redo the table without non-atomic values: I find this step is not needed because the solution is always the same and gets us to 3NF. student_subject table w/o non-atomic values roll_no name subject 101 Akon OS 101 Akon CN 103 Ckon Java 102 Bkon C 102 Bkon C++ 102 Bkon CN I begin with the table as it was. The non-atomic values can be only related to the student, such as with phone numbers. Or, they are an entity on their own. Determine which one. student_subject table roll_no name subject 101 Akon OS, CN 103 Ckon Java 102 Bkon C, C++, CN I believe the subject is an entity. Change student_subject to just student. student table roll_no* name 101 Akon 103 Ckon 102 Bkon Add a subject table subjectId* subject^ 1 OS 2 CN 3 Java 4 C 5 C++ Add a connecting table student_subject table roll_no*@ subjectId*@ 101 1 101 2 102 4 102 5 102 2 103 3