n a relation that describes a student, the student's classes should not be stored in one field, separated by commas. Rather, the classes should be moved to their own relation, which should include a link back to the student relation (called a foreign key).Second normal form (2NF) - A relation is in second normal form if it is in first normal form and each attribute is fully functionally dependent on the entire primary key. That is, no subset of the key can determine an attribute's value.Third normal form (3NF) - A relation is in third normal form if it is in second normal form and each non-key attribute is fully functionally dependent on the entire primary key, and not on any other non-key attribute. That is, no transitive dependencies exist among the attributes. A transitive dependency can be described as follows: "if A determines B, and B determines C, then A determines C."Boyce-Codd normal form (BCNF) - A relation is in Boyce-Codd normal form if it is in third normal form and all candidate keys defined for the relation satisfy the test for third normal form.Fourth normal form (4NF) - There should not exist any nontrivial multi-valued dependencies in a relation. To move from BCNF to 4NF, remove any independently multi-valued components of the primary key to two new parent entities. For example, if an employee can have many skills and many dependents, move the skill and dependent information to separate tables since they repeat AND since they are independent of each other.Fifth normal form (5NF) - By now, you've seen that normalization results in splitting tables from one table into two or more tables to eliminate anomalies. One tacit property of this splitting is that the designer could always reconstruct the original table by joining the new ones created during normalization. Fifth normal form differs from the definitions of the previous normal forms in that 5NF defines a goal to be reached, rather than the resolution of a particular...
